Bai You

Biodata

Power Progression

Background / History

Previous Life and Transmigration

Before arriving in Teyvat, Bai You was a recently graduated man living in a rented room on Blue Star. She had worked in a factory and played the game depicting Teyvat, where she was already fond of Varesa. While eating fish with pickled mustard greens, she abruptly found herself underwater in a petite girl’s body—with Varesa’s tail caught in her mouth 1 2 3 4 6.

Bai You recognized both Varesa and the world around her, but concealed her origins. She initially said she did not know how she had arrived; later, she told Varesa that she remembered nothing except her name. Her apparent amnesia was therefore a cover story rather than an actual loss of her previous memories 2 5 12.

Life with Varesa

Varesa offered Bai You shelter and clothing after learning that she had no home or family nearby. Their early time in Tide Song Cavern included building a snowman, swimming together, and discovering that Bai You could take a mermaid form resembling Varesa’s 5 9 10 11.

After hearing about the exile of Varesa’s parents and people, Bai You promised to help reunite them, even if powerful figures opposed her. The two exchanged Bond Necklaces before leaving the unfinished cavern residence for the Korolevsky Theater, where Odette welcomed Bai You 12 18 20 26.

Joining the Fatui

Using a system-provided invitation, Bai You sought an audience with the Tsaritsa and asked to become a Harbinger. She demonstrated her strength against Tartaglia, overwhelming him with a water-centered punch reinforced by the other elements 29 43 44 45 46.

Bai You then identified the Heavenly Principles as a common enemy. The Tsaritsa appointed her to the newly announced twelfth seat, with the codename Water Nymph. The other Harbingers accepted the appointment after learning of Tartaglia’s defeat, although Capitano expressed his intention to test her strength personally 46 47.

Dottore’s Attack and Recovery

Before a trip to Tide Song Cavern, the system warned Bai You that Dottore was approaching and calculated her chance of winning a direct fight at less than 1%. Although her reserves were considerable, her combat experience and command of the seven elements were insufficient 67.

Dottore dismantled her water attacks and defenses until she resorted to Annihilation Strike. When he retaliated against Varesa, Bai You used her Bond Necklace to teleport into the attack’s path, took his black spear, and confessed her feelings before losing consciousness. Her strike destroyed the attacking slice and tore through the cavern roof into the False Sky 69 70.

Bai You survived and recovered under Varesa’s care. She explained her Harbinger appointment and the circumstances of Dottore’s attack, then promised to discuss dangerous matters with Varesa rather than conceal them to spare her worry 77.

Mondstadt Journey

Bai You accepted Pantalone’s personal apology and two million Mora following Dottore’s actions. Later, while sailing toward Mondstadt aboard the Star Raft, she secretly arranged an unlimited Northland Bank credit line to fund a concert for Varesa 116 126 127.

During this period, Bai You and Varesa became increasingly open about their feelings. Bai You sang about the person she had been waiting to meet and admitted that the song referred to Varesa. They also visited the seaside, swam together in mermaid form, and chose two neighboring stars to represent themselves 125 142 145.

Liyue and Osial

After leaving Mondstadt, Bai You traveled south with Varesa through Stone Gate and the waterways leading to Liyue Harbor. They attended the Rite of Descension with Lumine and Paimon and witnessed Rex Lapis’s apparent assassination 167 169 170 173.

Her foreknowledge became an emotional burden as the crisis approached. She admitted to Varesa that she knew things she should not know, warned Lumine about Childe’s intentions, and struggled with knowing the destruction that would follow his failure to obtain the Gnosis 176 180.

When Childe released Osial, Bai You suppressed him using approximately half of her available Light Realm Power. Zhongli broke her suppression and explained that the crisis was a test of Liyue’s ability to protect itself. Bai You agreed to stand aside and later watched, in tears, as Ningguang prepared to sacrifice the Jade Chamber 183 185.

Appearance

• Build: Petite and youthful, with fair skin, slender hands, a small face, and a pointed chin. She estimates her new height at a little over 150 cm and no more than 160 cm; her previous body was 178 cm tall 1 3.
• Hair: Waist-length, pale blue-white hair, also described as white with cyan-tinted ends 3 4.
• Voice: A clear, soft young girl’s voice with a slight nasal quality, unlike her former deep male voice 2.
• Fin ears: Pale cyan-green ear fins remain after her first mermaid transformation. The system confirms that they cannot revert to human ears 13 14 17.
• Mermaid form: A luminous, scaled tail with translucent fins, generally described in azure-white or pale green tones 11 78 79 86.
• Cat forms: Phantom Cat gives her a creamy-white, shorthaired kitten form; her half-cat form adds cat ears and a fluffy tail to her human appearance 99 101.
• Clothing and styling: Commonly wears white or pale blue dresses. Varesa gives her flower-like hair clips and later styles her hair into ribbon-tied twin tails for a theater visit 2 8 37 105.

Personality

Bai You is easily flustered by Varesa’s attention, frequently blushing, stammering, or looking away when teased. Her early embarrassment also stems from adjusting to an unfamiliar body and clothing after transmigration. In private conversations with the system, she is much more blunt, sarcastic, and prone to profanity 2 4 5 6 14.

She enjoys food, sleep, affection, and playful activities such as building snowmen and experimenting with transformations. Her dependence on Varesa’s everyday care contrasts sharply with her willingness to confront danger: she promises to help Varesa’s family and instinctively shields her from Dottore’s fatal attack 9 12 69 77 84 95.

Bai You also worries about reciprocating the care she receives. Her concert plan grows from the feeling that Varesa has continually supported her while she has offered too little in return. Although she sometimes hides information to avoid causing worry, she becomes increasingly willing to share her fears and unusual knowledge with her lover 77 126 176.

Abilities & Skills

Sign-In System

Bai You is bound to a system that supplies talents, items, and information 4.

• Allows one sign-in per day, with additional rewards possible after ten consecutive sign-ins 4.
• Provides an inventory, lottery rewards, and mental communication 4 28.
• Can assess threats and trigger emergency measures, as it does before Dottore’s attack 67.
• Can accumulate unclaimed rewards and invest them into an existing talent 164.

Mermaid Physique

A mythic-grade talent centered on aquatic adaptation rather than combat strength 4 29.

• Freely switches her legs into a fish tail and back 4 11 13.
• Supports life on land and underwater in either form, including underwater breathing 4.
• Increases underwater movement speed by 300% in mermaid form 4.
• Grants supreme water affinity, strengthening the water-based attacks of her Primordial Body 4 45.
• Leaves her fin ears permanently visible after transformation 13 14.

Primordial Body and Light Realm Power

Initially grants independent control over Pyro, Hydro, Anemo, Electro, Dendro, Cryo, and Geo without a Vision or intermediary. Heavy use depletes elemental power and requires rest 29.

• Combines concentrated Hydro with smaller amounts of other elements to overwhelm Tartaglia 45 46.
• Shapes water into dragons and defensive shields 69.
• Becomes more precise through the ongoing influence of Capitano’s origin energy 113.
• At its utmost limit, accesses Light Realm Power directly instead of manipulating only its seven elemental branches 164.
• Provides Archon-level usable power, not immediate invincibility; the system distinguishes her authority and potential ceiling from the amount she can currently wield 165.
• Suppresses Osial with roughly half her available power, though Zhongli subsequently breaks that suppression 183.

Primordial: Annihilation Strike

A system-granted technique that releases the power Bai You cannot ordinarily bring fully to bear 67.

• Locks onto Dottore’s attacking slice and annihilates it despite its defenses 69.
• Tears through the cavern roof and cracks the False Sky 69.
• Causes overwhelming exhaustion and a stated two-day sleep requirement 67 69.

Phantom Cat

A transformation talent with freely selectable original, kitten, and half-cat forms 99.

• Self-transformation has no time limit, usage limit, or stated side effects 99.
• Allows individual feline features, including ears and a tail, to appear while she retains human form 99 101.
• Can transform another person through physical contact if they do not resist 99.
• A transformed target can return to their original form with a thought; strong resistance prevents the talent from taking effect 99.

Knowledge of Teyvat’s Events

Bai You retains knowledge from playing the game in her previous world 2 46.

• Uses her knowledge of the Heavenly Principles when negotiating with the Tsaritsa 46 47.
• Recognizes concealed identities and anticipates Childe’s attempt to obtain the Geo Gnosis and release Osial 179 180.
• Eventually tells Varesa that she knows many future events, though she remains anxious about how that knowledge will be received 176.

Equipment / Items

• Bond Necklaces: Paired gemstones engraved with their mermaid likenesses. Bai You wears Varesa’s cyan-blue likeness, while Varesa wears Bai You’s cyan-white likeness. They allow teleportation to the other wearer up to three times daily, within Bai You’s power. The system also describes conditional travel across timelines if the wearers are on different timelines 15 17 18 19.
• Spatial storage bag: Holds 1,000 cubic meters with no weight limit. Time is suspended inside; items within approximately two meters can be stored or retrieved by thought 40.
• Capitano’s origin energy: An ice-blue condensed energy sphere given for self-defense. While stored, it strengthens her elements and refines her control. It contains nearly half of Capitano’s original energy, a fact Bai You does not know 112 113.
• Thread of Fate: A mythic-grade, single-use item that makes a future event certain. It only affects events directly related to Bai You and cannot violate the world’s reasonable rules 28 29.
• Cat Transformation Candy: Two lottery rewards, each granting one hour in cat form and a 50% movement-speed increase. The candy form prevents elemental use and human speech 28 66.
• The Tsaritsa’s Invitation: A single-use audience pass to Snezhnaya Palace, obtained through the lottery 28 29.
• Object Fusion Device: A single-use reward that irreversibly combines fewer than five items into one 115.

Relationships

• Varesa — Lover, traveling companion, and the first person she meets in Teyvat. Their relationship develops through shared domestic life, exchanged necklaces, mutual confessions, and Bai You’s determination to protect her 1 18 69 125 176.
• Odette — Welcomes Bai You to the Korolevsky Theater, prepares her bed, and helps care for her. Postpones a performance during her recovery from Dottore’s attack 26 77.
• Columbina — Fellow Harbinger and theater guest who joins the group’s meals and evenings together. She recognizes and envies the warmth of Bai You and Varesa’s relationship 49 53 56 63.
• The Tsaritsa — Appoints Bai You as the twelfth Harbinger after her demonstration against Tartaglia and discussion of the Heavenly Principles 43 45 46 47.
• Capitano — Senior colleague who notices her unstable elemental control and gives her condensed origin energy for protection 47 112 113.
• Pantalone — Provides an apology and compensation after Dottore’s actions, then finances Bai You’s planned concert for Varesa in exchange for a request that she save him cigars 115 116 127.
• Tartaglia / Childe — Defeated opponent and fellow Harbinger. Bai You later warns Lumine about his plans; he witnesses her suppression of Osial and recognizes that her strength is beyond his reach 45 46 180 183.
• Dottore — Attempts to seize her as an experimental subject. His attacking slice is annihilated, but its final attack nearly costs Bai You her life when she protects Varesa 67 69.
• Lumine and Paimon — Companions during Liyue’s ceremonies. Bai You warns them that Childe’s assistance serves his own pursuit of the Gnosis 173 180.
• Zhongli — Reveals the purpose of Liyue’s trial after breaking Bai You’s suppression of Osial. She agrees not to intervene further 183.

Notable Quotes

“From now on, this won't be yours to worry about alone.” 12

“I know a lot of things I shouldn't know. And I also know a great, great many things that are going to happen.” 176