Xingsu

Biodata

Background / History

Origins and the House of the Hearth

Xingsu was created by the Memokeeper Lin, who sent him and other versions of him across the universe to collect stories and memories. He entered Teyvat as a child falling from the stars and was discovered in the snow in Snezhnaya. He knew nothing of his origins and possessed only his clothes and a necklace; examinations found no apparent difference between him and an ordinary human 1 17.

The Fatui placed him in the House of the Hearth, where Clervie became his first friend. He also befriended Peruere, taking an interest in her unusual eyes and helping feed her pet spiders. His exceptional aptitude for languages, memorization, and swordsmanship attracted Crucabena’s attention, and she transferred the three children to a harsher training environment. Other children treated his attempts to help them as provocations, leaving the trio increasingly isolated 1 6.

Crucabena eventually forced Xingsu, Clervie, and Peruere to kill defeated children during combat practice. Xingsu condemned the House’s transformation into a fighting pit and began considering rebellion. He wanted it to become a genuine home rather than a place where friends would eventually be forced to kill one another 2 3.

Rebellion and Death

Xingsu and Peruere agreed that Crucabena had to die, but their attempt to secure Clervie’s help failed because she could not betray her mother. Peruere subsequently revealed the dangerous power and spreading curse within her body, while Xingsu shared what little he knew about his arrival and Dottore’s examination of him. Despite their uncertain prospects, they agreed to fight for a future together 7.

During the Hunting Game, Xingsu deliberately headed east, reasoning that Crucabena would intercept him before he could encounter outsiders. He rejected her authority and attacked her directly. His reactions and swordsmanship sustained dozens of exchanges, but exhaustion and Crucabena’s superior strength eventually left him disarmed. She threatened to have Dottore alter his thoughts and rendered him unconscious with a drugged handkerchief 9 10.

When Xingsu awoke to find Peruere losing her battle with Crucabena, he forced himself upright and attacked with his broken sword. Crucabena stabbed him through the chest. Unable to speak, he mouthed “You can do it” to Peruere before dying. She later buried him with the jar of paper stars she had made for him 12 13 14.

A farewell letter he had written remained among Arlecchino’s most carefully guarded possessions years later 59.

Reconstitution in Sumeru

Nahida discovered an unusually bright memory of Xingsu within Irminsul and added her power to give it form. He returned with his appearance intact but remembered only his name and a conviction that he came from beyond Teyvat. His first word to Nahida was “Mother” 15.

Nahida offered him a home in Sumeru and the status of a traveling scholar. She taught him to read at the House of Daena, where he mastered the literacy primers within hours and subsequently found work as a librarian. Lin then contacted him mentally, explained his creation and previous death, and identified his extraordinary learning ability as a blessing of memory 15 17 19.

Eleazar Research and the Wisdom Network

After meeting Tighnari and Collei, Xingsu perceived a black mist surrounding Collei. Touching it relieved her Eleazar symptoms but exposed him to the pain and despair contained within it. He continued treating her despite this cost and made finding a cure one of his principal reasons for remaining in Sumeru 19 25 33.

Over several months, Xingsu studied across the Akademiya’s disciplines and developed a theory connecting Eleazar to manifested negative memories. His paper was initially rejected and mocked, but a demonstration before Tighnari, Nafis, and Amurta scholars produced a confirmed cure in a patient. Nafis offered to take him as a student; Xingsu declined 28.

His second paper, Building the Wisdom Network, proposed adapting Akasha technology for direct communication between people. The proposal drew religious objections from conservative scholars and political opposition from the Grand Sage’s faction. Xingsu nevertheless pursued an independent system, eventually producing communication devices that no longer depended on the Akasha’s core permissions or message filtering 28 31 34.

Exile and Life in Fontaine

Azar branded Xingsu a heretic, and he became wanted by the Akademiya. Cyno helped him reach Caravan Ribat, where Dottore trapped his consciousness and attempted to examine his memories. Lin destroyed the projection and freed him. Dehya then guided him into the desert, while Candace concealed and sheltered him in Aaru Village 37 38 41 43.

After reaching Fontaine, Xingsu struggled to find employment because he lacked credentials and proof of his scholarly identity. He intervened when Furina was threatened by a masked woman, unknowingly encountering Peruere—now Arlecchino. He felt an intense familiarity with her but could recover no memory of their shared past 43 44 45.

Furina entrusted his accommodation to Clorinde, who arranged an introduction to Callas and Navia in Poisson. Callas allowed him to stay under observation and later employed him as a mechanic. Under engineer Yvette’s supervision, Xingsu quickly mastered the work, repairing everything from fishing equipment and toys to transmission components and housing foundations 45 47 48 50.

Arlecchino subsequently secured a meeting with him through material assistance to Poisson. Although Xingsu initially resisted contact with another Harbinger, he agreed to speak with her. He described his persecution in Sumeru and the theft of his research after reaching Fontaine. Arlecchino learned that he had lost his memories and concealed their shared history, believing that a peaceful life away from the House of the Hearth would be best for him. Her guarded responses nevertheless strengthened his suspicions, and he asked whether they had met before 51 52.

Recovery of His Memories and Return to the Hearth

Xingsu left Poisson to investigate his past and recover his necklace with Lin’s guidance. During his return to the Court of Fontaine, he encountered a vendor selling suspicious L㏒s, recognized signs of addiction in a customer, and reported the seller to the Maison Gardiennage. Continuing his search, he helped Earnshaw retrieve his runaway puppies before reaching two carefully tended, nameless graves at night. Lin located the necklace beneath a flower, though Xingsu initially hesitated to disturb the site 54 55 57.

By dawn, Xingsu had recovered his necklace and all his memories. He accepted Lin’s suggestion that this day become his birthday, marking the beginning of his new life. Lin treasured the memories of his childhood friendships and, as part of their transaction, bestowed new power over his memories while starlight touched the Cryo Vision in his palm. The previously overwhelming recollections became ordered, allowing him to face his past without being swept away by it 59.

After returning to Arlecchino, Xingsu read her memories with her cooperation. He witnessed her awakening of a Vision, victory over Crucabena, trial in Snezhnaya, and solitary assumption of responsibility for the household. This also revealed the farewell letter he had left her. Their renewed connection developed into a romance 63 66 96.

Xingsu became the House of the Hearth’s special instructor, winning the children’s affection through humorous, patient explanations of practical combat. He also continued refining his communications technology, modifying a pair of earpieces and preparing complete research manuscripts. Recognizing that further development required resources, materials, and experimental facilities, he addressed one manuscript to the Fontaine Research Institute 67 69.

Fontaine Investigations and Morning Star

Xingsu’s concern for the household’s children drew him into investigations of exploitation and corruption. After witnessing the suffering of a wounded girl, he killed Daerdufu and read his memories, uncovering the merchant’s use of charity and abused children to secure noble patronage. Rather than treating Daerdufu’s death as a complete solution, Xingsu proposed using the evidence to obtain the Court of Fontaine’s backing against the wider network. He asked Freminet to gather help for the victims, while Arlecchino agreed that the household could shelter more homeless children. The wounded girl subsequently died, and the two mourned her together 73 75.

Neuvillette offered him research support and honorary researcher status at the Fontaine Research Institute. Xingsu accepted in order to consult Alain and Rene’s surviving manuscripts. Their journey was interrupted by an explosion at the institute that destroyed Aquabus track supports; Neuvillette carried Xingsu and the Melusine guide safely to shore with Hydro. The disaster ultimately obstructed the proposed collaboration 78 105.

His investigations also extended to L㏒s distribution, coercion of dealers’ families, and child trafficking. He obtained a letter of introduction to Valerius’s underground hideout and subdued its armed guards at close range 86 89 90.

During this period, Xingsu discovered that Clervie was alive as the pastry chef Claire. Her forgotten connection to him began surfacing through fragments of memory, and the childhood friends eventually reunited. He sought a precious memory that could be traded for a chance for Clervie to live on; Escoffier later credited him with saving her 86 89 93 96 105.

His extralegal activities became associated with the name Morning Star. Charlotte regarded him as a widely discussed hero, while Chevreuse remained determined to arrest him. Furina described the contrast between his gentleness and his fierce, decisive actions unconstrained by social rules 102 105.

Supporting Poisson and Leading the Household

Following Callas’s death in a judicial duel, Xingsu claimed his remains as a member of the Spina di Rosula and mourned him with a final offering of fire-water. He then stayed in Poisson to help Navia manage the town and stabilize the organization. He intervened against malicious interference while leaving some difficulties for Navia to resolve herself as experience 109 110.

When opponents spread an invented story about his relationship with Callas and intentions toward Navia, Xingsu stopped the rumors discreetly. Clervie and the children brought supplies, which Navia accepted after his reassurance. Once Poisson’s situation stabilized, he returned to the Court of Fontaine with them, carrying a box of macarons Navia had baked for him 110.

Back at the House of the Hearth, Xingsu handled its affairs from Arlecchino’s office during her absence in Snezhnaya. His responsibilities extended beyond instruction to household administration and field leadership 111 120.

Liyue and the Chasm Rescue

Xingsu enlisted Lumine to help retrieve Fatui troops stranded in the Chasm. Ningguang allowed the operation under Yelan’s supervision. Traveling with Lumine and Paimon, he helped assess an injured miner before continuing into the Underground Mines 118.

He presented Arlecchino’s token to the starving Ninth Company, identified himself as a head of the House of the Hearth, and ordered the soldiers to stand down. He explained that Nikolay’s letters had alerted him to Katarina’s group and defended the abandoned troops’ service against Abyss monsters. He prepared proper food for them, astonishing Lumine and Paimon by producing a live dairy cow from his magic pocket 120.

Yelan offered help locating the person he sought in exchange for the withdrawal of the Ninth Company and other Fatui operating in Liyue’s wilderness. Xingsu later stated that he had recovered the child who was his principal reason for coming to Liyue 123 130.

When his association with the Fatui alarmed Tighnari, Xingsu explained that he had joined voluntarily, served Arlecchino, and shared her opposition to Dottore’s actions. He ordered the soldiers accompanying him to lower their weapons and assured Tighnari that they would not become enemies 125 126.

During his time in Liyue Harbor, he helped Teucer find Tartaglia, played pirates with local children, toured the city with Hu Tao, and bought gifts for Arlecchino and the children. He also warned Tartaglia against seeking a fight with Zhongli and agreed to a future match if he had time 112 114 129 130.

Later Travels and Return to Sumeru

In Snezhnaya, Xingsu and Arlecchino visited Odette to explain Rosalyne’s final gift, the Fire of Two Worlds. Xingsu left the decision to erase her Fatui-related memories entirely to Odette and encouraged her to make that choice at Rosalyne’s grave 138.

On returning to Sumeru, he again treated Collei’s Eleazar. She reacted painfully to his admission that he had joined the Fatui and asked him to leave so she could be alone. He subsequently informed Lumine, Paimon, and Tighnari that Dottore and Azar’s plan to create a god was nearing completion, and offered to guide the travelers to Sumeru City 142.

Within the repeating dream of the festival, Xingsu discovered that the Akasha was harvesting people’s dreams and memories as computing power and energy for the god-creation project. He could leave the dream, but returned after realizing that forcibly removing the sleepers’ terminals could permanently damage their minds. Attempts to expose the truth or erase Scott within the dream failed to alter the repeating system. As Dunyarzad weakened under Eleazar and repeated memory extraction, he prepared to confront the Akademiya before Nahida appeared 151.

Xingsu continued trying to help the unconscious Dunyarzad, whose condition Nahida attributed to exhaustion and the strain of the loops. During their conversation, Nahida counted approximately three thousand days since his birth from Irminsul and consequently called him an eight-year-old, to his disbelief 154.

He later confronted Scaramouche within a dream. Initially avoiding combat, he ultimately countered an Electro-charged attack and restrained him with a dagger. After recognizing that the dream reflected Scaramouche’s past and attachment to a child, Xingsu warned him against Dottore. Scaramouche rejected the warning and insisted on pursuing godhood, after which Xingsu dissolved out of the dream 158.

Appearance

• Star-shaped pupils: His most distinctive feature; Arlecchino specifically tells Lyney and Lynette to look for someone with star-shaped eyes 13 43.
• Slender build: He is described as slight or frail-looking, which leads others to underestimate his fighting ability 12 31 41.
• Youthful appearance: His delicate skin causes one prospective Fontaine employer to doubt his suitability for physical work; another describes him as handsome 43.
• Clothing preferences: He favors purple and yellow, a combination criticized during his search for work in Fontaine and later by Chiori 43 105.
• Greater composure: At their formal reunion, Arlecchino observes that he has lost his childhood awkwardness and gained the composure of a traveler, while retaining the same strength and hope in his eyes 52.

Personality

Xingsu is compassionate but strongly opposed to coercion. At the House of the Hearth, he comforts and tends to Clervie while rejecting Crucabena’s insistence that survival requires killing his friends. Even after defeat, he refuses to accept her authority or the future she has chosen for him 2 3 9 10.

His curiosity develops into a rigorous scholarly outlook after his return to life. He studies across disciplinary boundaries, checks evidence himself, and follows Nahida’s warning against surrendering independent thought to the Akasha. Alhaitham particularly values his combination of intellectual discipline, kindness, and willingness to bear another person’s suffering 17 21 29.

He frequently jokes with Peruere and Lin, using teasing and sarcasm even during uncomfortable conversations. This lightness coexists with deep uncertainty about his identity: after recognizing Scott’s familiarity with him, he fears that his forgotten connection to the Fatui might mean he once inflicted suffering like Collei’s 3 7 23 24 35.

His dedication can become self-neglect. Secret research trips leave him visibly thinner, short of food, and exhausted, yet he continues experimenting and treating Eleazar patients despite institutional hostility 25 31 41.

Recovering his memories allows him to reconcile with his past rather than remain defined by it. He accepts the day of their awakening as a celebration of his new life, while continuing to value the friendships and hopes formed during his childhood 59.

As an instructor, he is patient, approachable, and careful not to humiliate children for mistakes. His engaging lessons contrast with the harshness of earlier instructors, and he encourages even capable children such as Lyney to rely on the adults around them 67 105 107.

His kindness does not exclude lethal violence. He kills Daerdufu for his exploitation of children and seeks to dismantle the system protecting him, rather than accept the removal of one offender as sufficient. This willingness to act outside legal constraints underlies the divided responses to Morning Star 75 102 105.

He respects personal choice even when memories and painful loyalties are involved. In Odette’s case, he explains Rosalyne’s intentions but refuses to decide whether she should erase her memories. Despite taking on leadership duties, he dislikes the convolutions of diplomacy and politics and generally leaves those matters to Arlecchino 118 138.

Abilities & Skills

Blessing of Memory

Lin attributes Xingsu’s exceptional learning ability to his nature as a child of memory 17.

• Memorizes material after very few readings and learns sword techniques in a day that take other children a month 1.
• Masters literacy primers within hours and retains detailed research after approximately an hour of reading 17 21.
• Develops broad knowledge across the Akademiya’s disciplines, including languages, elemental theory, history, mechanisms, and circuitry 22 28 29.
• Can identify flaws, outdated conclusions, and useful references within the House of Daena’s collection 28.
• Can sense exceptional differences in the scale of others’ memories; he perceives Neuvillette’s as vastly exceeding those of an ordinary person 79.
• Limit: Exceptional retention does not make him immediately knowledgeable. After reconstitution, he must relearn language, everyday survival, and social knowledge 15 16 17.

Memory Perception and Absorption

Xingsu can perceive and absorb the black memory mist associated with Eleazar, accessing the emotional suffering and fragments of experience within it 19 23 33.

• Relieves Collei’s symptoms and stabilizes a flare-up when her usual medicine fails 19 25.
• Demonstrates a confirmed cure in another Eleazar patient before Amurta scholars 28.
• Uses these experiences to investigate negative memories as a cause of the disease 21 28.
• Returns to treating Collei after his later travels 142.
• Cost: Absorption exposes him to pain, fear, despair, and mental strain 20 25.
• Limits: His treatment depends on a unique power that others cannot reproduce. Lin also states that they cannot simply delete the encrypted memories 23 26.

After recovering his past, Xingsu gains more direct control over memories. Lin’s gift orders his own recollections and prevents their emotional weight from overwhelming him 59.

• Reads Arlecchino’s memories through contact after asking her to relax and cooperate, witnessing events that occurred after his death 63.
• Reads the dying or newly dead Daerdufu’s memories to uncover evidence of exploitation and noble involvement 75.
• Limits: Arlecchino’s reading is performed with her cooperation; this scene does not establish unrestricted access to every person’s memories 63.

Swordsmanship and Close Combat

House of the Hearth training gives Xingsu precise swordsmanship, fast reactions, and practical combat instincts 1 9.

• Targets vital points and adapts quickly to incoming attacks, including Crucabena’s Hydro lances 9.
• Forces Crucabena into dozens of exchanges when most children fall to her within three moves 9.
• Retains combat instincts after losing his autobiographical memories, instinctively defeating a squad of mercenaries 31 33.
• Participates in a coordinated ambush that kills a Consecrated Beast during his desert travels 47.
• Completes reaction training with all targets hit 61.
• Reverses an armed ambush in approximately half a second, seizing a gun aimed at his back while bringing a concealed dagger to the hideout leader’s neck 90.
• Effortlessly blocks Chevreuse’s forceful polearm strike with one raised arm 102.
• Within Scaramouche’s dream, evades lightning blades, redirects the force of an Electro-charged punch, and restrains Scaramouche with a dagger 158.
• Limits: He has no Vision during his rebellion and cannot overcome Crucabena’s strength, experience, and elemental abilities 3 9.
• Contextual qualification: His confrontation with Scaramouche occurs in a dream and does not by itself establish an identical outcome in a waking battle 158.

Engineering and Communications

Xingsu combines mechanical knowledge with his study of the Akasha to develop communication technology and perform practical repairs 27 28 50.

• Reverse-engineers the Akasha’s underlying signal-encoding logic 28.
• Develops communication devices independent of the Akasha’s central hub and permission restrictions 34.
• Learns unfamiliar repair procedures from a blueprint and brief demonstration, earning Yvette’s approval for work without detectable oversights 50.
• Modifies a pair of communication earpieces 67.
• Organizes his theoretical framework, energy-conduction formulas, and structural models into complete research manuscripts 69.
• Technical setbacks: Early Ley Line transmissions work only toward Irminsul; initial wireless experiments suffer from inadequate coverage and burned-out chips 31.
• Resource limits: Further development requires institutional-scale materials, funding, and experimental space; his proposed Fontaine Research Institute collaboration is obstructed by its explosion 69 78 105.

Connection to Lin

Xingsu communicates with Lin through an internal mental link. She can review his memories and experience sensations indirectly through them, including the taste of food 17 18 23.

• Lin identifies the black mist he absorbs as encrypted information carrying intense negative emotions 23.
• She explains why his combat instincts survived his memory loss 33.
• She intervenes when Dottore invades his consciousness, destroying the prison and warning him to protect his memories 37.
• She guides him to his missing necklace and later grants him new control over his memories 57 59.
• Limit: Her destruction of Dottore’s prison is Lin’s action, not a demonstrated ability Xingsu can independently reproduce 37.

Cryo Vision

Xingsu possesses a Cryo Vision by the time his memories are restored. Lin’s starlight touches it while she grants him new power over his recollections 59.

• Distinction: The memory-control gift is explicitly associated with Lin’s intervention; the scene does not establish that all his memory abilities originate from the Vision 59.

Dream Navigation and Manipulation

During the repeating festival dream, Xingsu can recognize the system’s nature, leave it, and return to the sleepers’ shared predicament 151.

• Identifies the harvesting of dreams and memories for the god-creation project 151.
• Attempts to expose the system and erase Scott within the dream 151.
• Enters a dream reflecting Scaramouche’s past, interacts with its inhabitants, and departs by dissolving into the air 158.
• Limits: His alterations do not stop the festival loops. Forcibly disconnecting the sleepers from their Akasha Terminals risks permanent mental injury, preventing a simple physical rescue 151.
• Medical limits: Despite repeated efforts, he cannot immediately awaken the exhausted Dunyarzad 154.

Instruction and Leadership

Xingsu combines practical combat instruction with explanations drawn from his scholarly studies and travels. He breaks difficult techniques into accessible steps and corrects mistakes patiently 67 107.

• Wins the affection and trust of the House of the Hearth’s children in his first afternoon of teaching 67.
• Shares responsibility for discipline with Arlecchino, with the two adopting complementary gentle and stern roles 106.
• Handles household paperwork and administration during Arlecchino’s absence 111.
• Uses her token and his household position to command the Ninth Company and de-escalate confrontations 120 126.
• Helps Navia stabilize Poisson while allowing her opportunities to develop her own leadership 110.

Power Progression

Equipment / Weapons / Items

• Star-shaped necklace — Present when he first arrived in Teyvat. Its pendant resembles a star outlined in metal and contains tiny points of light. He gives it to Clervie during the Icemelt Festival; after his reconstitution, Lin notes its absence and later locates it somewhere in Fontaine. He subsequently finds it at the nameless graves and has recovered it by the dawn when his memories awaken 1 5 18 43 57 59.
• Jar of 999 paper stars — Handmade by Peruere as an Icemelt Festival gift. Xingsu treasures it, and Peruere later buries it with his body 5 6 14.
• Sword — His weapon during the rebellion against Crucabena. He retrieves its broken remains for his final attempt to protect Peruere. He also carries a sword during his later Chasm expedition 9 12 123.
• Akasha Terminal — Initially assists his literacy studies. He removes it after Nahida’s warning, later studying its hardware and operating principles for his communications research 17 27 28.
• Akasha radio-frequency chips — Restricted components obtained through Dori for his wireless experiments; their limited quantity and coverage constrain early testing 30 31.
• Cryo Vision — In his possession when Lin grants him new control over his memories 59.
• Communication earpieces — A pair he spends the night modifying shortly before beginning his teaching duties 67.
• Research manuscripts — Two organized copies of his communications research, including theoretical and structural material; one is addressed to the Fontaine Research Institute 69.
• Concealed dagger — Used in close-quarters operations, including the reversal of an armed ambush and his confrontation with Scaramouche in a dream 90 158.
• Arlecchino’s token — Establishes his authority before the Ninth Company in the Chasm 120.
• Magic pocket — Stores supplies and can accommodate a live dairy cow, which he produces to provide milk for the rescued Fatui 120.
• Farewell letter — Written before his death and preserved by Arlecchino in a locked drawer; he later sees it while reading her memories 59 63.

Relationships

• Peruere / Arlecchino — Childhood friend, partner in rebellion, and later romantic partner. She makes his paper-star gift and mourns and buries him after his death. On discovering that he has returned, she conceals a report about him from the Harbingers and later orders discreet observation without contact. Xingsu initially feels a powerful familiarity with her without recognizing her. She conceals their past at their formal reunion to protect his peaceful new life, but after his memories return they reconnect, share responsibility for the household, and become lovers. She credits him with easing her burdens, while he repeatedly encourages her to rely on him 5 7 12 14 31 44 46 52 59 63 96 106.
• Clervie / Claire — His first friend in the House of the Hearth. He comforts her after Crucabena’s abuse and gives her his necklace, but their rebellion places her between her friends and her mother. He later discovers her living as the pastry chef Claire, recognizes that her kindness has survived her memory loss, and reunites her with Arlecchino. He seeks a precious memory to exchange for a chance for her to live on, and Escoffier later identifies him as her savior. Clervie supports his relationship with Arlecchino and helps care for the household’s children 1 2 5 7 86 89 93 96 105 110.
• Lin — His creator and continuing mental companion. Their exchanges are often irreverent, but she explains his nature and protects him from Dottore’s intrusion. She helps him locate his necklace, treasures the story of his childhood friendships, grants him greater control over memory, and teases him about his feelings for Arlecchino 17 23 24 33 37 57 59 66.
• Nahida — Restores him to physical form, teaches him to read, and guides his new life in Sumeru. He initially calls her “Mother” and later becomes concerned by her unexplained absences. They meet again during the festival dream crisis, when she helps explain Dunyarzad’s condition and insists that Xingsu is still a child when counting from his reconstitution 15 17 41 151 154.
• Crucabena — Abusive guardian, instructor, and eventual killer. She prizes his talent but seeks to force him into becoming her chosen king 1 9 10 12.
• Dottore — Examines Xingsu after his arrival and remains interested in his origins. His later attempt to inspect Xingsu’s memories is stopped by Lin. Xingsu continues to oppose him despite joining Arlecchino’s faction, exposes his involvement in the god-creation project, and warns Scaramouche against relying on him 7 37 126 142 158.
• Collei — Patient and central inspiration for his Eleazar research. Witnessing her memories strengthens his determination to help her; she, in turn, hopes to become as gentle and kind as him. Tighnari describes him as a guardian-like source of support for her. His later Fatui affiliation strains their relationship, and she asks for solitude after he confirms that he joined 19 33 41 141 142.
• Tighnari — Medical and scholarly ally who requests Xingsu’s help treating Collei and worries about the cost to his health. He initially fears Xingsu has been brainwashed after learning of his Fatui association, prompting Xingsu to explain his voluntary loyalty to Arlecchino and continuing hostility toward Dottore. Tighnari later welcomes him back to Sumeru 20 25 26 126 142.
• Alhaitham — Recognizes his scholarly ability, offers assistance, and supports his independence from the Akasha 21 22 28 29.
• Dori — Supplier of restricted research components and an investor in his work. An accidental mercenary confrontation leads her to waive his outstanding balance 30 32 41.
• Cyno, Dehya, and Candace — Help protect his escape from Sumeru through an arranged escort, desert guidance, and refuge in Aaru Village 37 38 39.
• Furina and Clorinde — Furina arranges help after he intervenes during her attack; Clorinde questions him, secures temporary lodging, and introduces him to his protectors in Poisson. Clorinde later acknowledges him as a good person despite sensing danger in him, while Furina emphasizes the contrast between his considerate nature and fierce methods 43 45 46 47 105.
• Callas — Grants him conditional shelter, instructs him to keep a low profile, and provides his mechanic’s job. After Callas dies in a duel, Xingsu claims his body, mourns him, and supports Navia’s succession 47 48 50 109 110.
• Navia — Quickly befriends him through his travel stories, invites him to play Tabletop Troupe and join the Spina di Rosula, and bakes macarons with him. She later calls recruiting him one of her best decisions. After Callas’s death, he helps her stabilize Poisson and protects the organization while encouraging her development as a leader 47 49 105 110.
• Yvette — Supervises his initial mechanical work. Her skepticism gives way to approval after he rapidly masters the procedures 50.
• Lyney and Lynette — Pupils and trusted helpers in the household. He asks them to assist with a magical surprise for Arlecchino, admires Lyney’s imagination and familial devotion, and values Lynette’s perceptiveness. Their curiosity about his romance sometimes earns them extra training 67 105.
• Freminet — Pupil whose mechanical talent and hidden strength Xingsu values. Freminet praises his ideas, patience, and care, and assists him with relief efforts and supplies for Poisson 75 105 110.
• Neuvillette — Offers research support and an honorary position at the Fontaine Research Institute, and saves him during the institute explosion. Their correspondence includes Xingsu’s criticism of administrative inefficiency. Xingsu also perceives the extraordinary scale of his memories 78 79 105.
• Chevreuse — Pursues Morning Star despite recognizing the conflict between protecting the weak and arresting someone who has acted on their behalf. Xingsu blocks her attempt to subdue him, and she remains determined to catch him 102 105.
• Charlotte — Repeatedly seeks an interview about Morning Star, while Xingsu refuses and complains about her lack of boundaries 105.
• Escoffier — Clervie’s former teacher, who encounters him at Claire’s bakery and later expresses gratitude for his role in saving her pupil 105.
• Lumine and Paimon — Companions during the Chasm rescue and later allies in Sumeru. He hires Lumine to help retrieve the stranded Fatui, explains his household connections, and later shares information about the god-creation project 118 120 142.
• Yelan — Monitors his Chasm expedition on Ningguang’s orders and offers assistance under conditions restricting further Fatui activity in Liyue 118 123.
• Katarina, Anton, and the Ninth Company — Stranded Fatui whom he feeds and leads out of their immediate crisis, using Arlecchino’s token to establish authority. Nikolay’s letters alert him to Katarina’s group 120.
• Tartaglia and Teucer — Helps Teucer find his brother and treats the child warmly. His interactions with Tartaglia combine teasing criticism of his actions in Liyue, warnings against challenging Zhongli, and a conditional promise of a future spar 112 114 129 130.
• Hu Tao — Guides him around Liyue Harbor and helps with shopping for household gifts, while her funeral-related suggestions frequently unsettle him 129.
• Odette — Receives his counsel concerning Rosalyne’s final gift. He encourages her to decide for herself whether to erase her memories of the Fatui 138.
• Dunyarzad — Trusts him during the repeating festival dream despite their brief acquaintance. Her deteriorating condition intensifies his determination to stop the exploitation of the sleepers 151 154.
• Scaramouche — Confronts him in a dream and rejects his warning about Dottore. Xingsu recognizes the importance of the child appearing in the dream but fails to dissuade him from pursuing godhood 158.

Notable Quotes

“Clervie, have you ever thought how wonderful it would be if the House of the Hearth were truly a warm home? Everyone could gather around the hearth telling stories, eat together, play together, share with one another, and work together toward the same ideal.” 2

“Is the survival you preach built on the piled-up bones of children?!” 9

“You can do it.” — His final encouragement to Peruere before his death 12

“Have I... met you before?” — To Arlecchino during their formal reunion 52

“Heh, yes. What a wonderful day. It couldn’t be more fitting for celebrating my new life.” — On adopting the day his memories awaken as his birthday 59

“Tighnari, what I’m trying to say is that we’ll never be enemies, not in the past or in the future.” 126