Subaru Natsuki

Biodata

Feature	Value
Name	Subaru Natsuki (菜月昂)
Alias(es)	486
Gender	Male
Affiliation	Uchiha Yu (disciple); Emilia's camp
Occupation/Role	Yu's disciple; Emilia's guard and briefly appointed knight
Status	Alive
First Appearance	403

Power Progression

Stage / Realm / Level	Chapter	Notes
Single-Tomoe Sharingan	405	Yu empowers Subaru's eyes, allowing him to perceive an opponent's movements as slowed and evade Felt's attacks.
Iron Body	412	Completes initial training in Yu's Six Powers technique; his body becomes hard as iron following extreme accelerated training.
Basic kicking technique	412	Reaches roughly halfway through its foundational training alongside Iron Body.
Chakra affinities and ninjutsu training	414	A chakra test reveals five affinities; Yu teaches him Shadow Clone Jutsu and demonstrates techniques Subaru can copy with the Sharingan.
Summoning Technique	416	Learns to use Yu's summoning method and receives scrolls connected to the Nine Tailed Beasts.
Practical chakra combat	418 421	Uses Shadow Clones in combat and summons all nine Tailed Beasts; later receives direct combat and chakra-control instruction from them.
Soru basics	422	Completes the initial training for Soru, greatly improving his movement speed.
Three-Tomoe Sharingan	427	Awakens the Three Tomoe upon his first documented death.
Mangekyo Sharingan	430	Awakens after repeated deaths and Emilia's murder; grants mastery over pain and a major increase in ocular power.
Susanoo	430	Manifests Susanoo and defeats the White Whale with ease.
Pain manipulation	432	Uses his left Mangekyo ability to perceive, extract, and amplify Petelgeuse's buried pain.
Jonin-level chakra reserves	438	His reserves reach approximately jonin level; Susanoo's immense cost is offset by the witch aura within his body.

Background

Subaru is an otherworldly youth burdened by Return by Death, repeatedly dying while trying to save Emilia. He initially considers himself a “worthless loser” with a useless cheat ability, but discovers he can discuss that ability without the familiar constriction in his chest after meeting Yu. 403

Yu accepts Subaru as his disciple, but establishes a strict condition: Subaru must accomplish his goals through his own efforts, while Yu's role is only to make him stronger. Subaru immediately struggles with this lesson; his panicked call for guards against local thugs ruins Yu's intended combat lesson. 404

At Roswaal's manor, Yu subjects Subaru to accelerated and punishing physical training. The process establishes Iron Body and foundational kicking ability in a single day, transforming Subaru from an ordinary youth into a capable fighter. 411 412

Personality

Subaru is impulsive, emotional, and intensely protective of Emilia. His devotion drives him to face threats he knows he cannot defeat, endure Yu's brutal training, and repeatedly pursue outcomes that protect Emilia and others. 407 411 421

He can be boastful and jealous, particularly around Emilia, and his recklessness causes political harm during the royal selection. Emilia directly confronts him for prioritizing his own grandstanding over the support she actually needs. Subaru later recognizes his weakness and resolves to help her more responsibly. 422 425 426

Repeated deaths and the Mangekyo's awakening make him markedly calmer, colder, and more perceptive. Despite this change, his central motivation remains Emilia's kindness toward him when he was powerless and desperate. 430 431 434 435

Abilities & Skills

Return by Death

Subaru returns to an earlier point after dying. His repeated deaths are tied to the growth of his ocular abilities, though the suffering remains psychologically severe. 403 421 427 430

• Reawakens after death with accumulated memories of prior timelines.
• Enables him to retry events and pursue better outcomes.
• His suffering and deaths contribute to his Sharingan's evolution. 421 427 430
• The witches seek to exploit this ability to create their own “perfect ending,” a prospect Subaru rejects. 441

Sharingan

Yu grants Subaru unusual ocular power. The Sharingan improves his perception and lets him copy ninjutsu, but initially exceeds the limits of Subaru's untrained body. 405 407 414

• Perceives attacks at a slowed pace and reads combat movements. 405 407
• Copies ninjutsu demonstrated by Yu. 414
• Reaches Three Tomoe upon death, then evolves into the Mangekyo Sharingan after repeated trauma. 427 430
• Its crimson appearance can frighten observers, including Otto. 432

Mangekyo Sharingan

Subaru awakens the Mangekyo after finding Emilia murdered and being killed by Puck. Its power changes his relationship with pain, leaving him calm in situations that once broke him. 430

• Pain mastery — Allows Subaru to endure and control pain; he uses it to turn Petelgeuse's hidden suffering against him. 430 432
• Emotion perception — Sees the emotions and concealed pain within others, exposing Roswaal's motives and reading Petelgeuse's trauma. 432 439
• Pain amplification — Extracts and magnifies a target's pain; Subaru's first use drives Petelgeuse to suicide before the ability is fully controlled. 432
• Susanoo — Summons a powerful ocular manifestation capable of defeating the White Whale. 430
• Limitation — Susanoo requires enormous chakra expenditure; Subaru relies on the witch aura within his body to use it casually. 438

Six Powers

Yu trains Subaru in techniques from his own world. 412 422

• Iron Body — Hardens Subaru's body to iron-like durability. 412
• Soru — Grants explosive movement speed; Subaru uses it nearly at its limit while rushing to Roswaal's estate. 422 430
• Kami-e — Identified as one of the Six Powers Subaru is training to learn. 422

Ninjutsu

Subaru possesses chakra, five chakra affinities, and a growing repertoire of hand-seal techniques. 414

• Shadow Clone Jutsu — Creates physical clones for training, misdirection, scouting, and rescue operations. 414 418 434
• Summoning Technique — Uses Yu's scroll to summon the Nine Tailed Beasts through a joint contract. 416 418
• Uses clones and martial ability together to outmaneuver Julius in a sparring match. 423

Combat Skill

Subaru develops from a physically ordinary youth into a versatile combatant under Yu and the Tailed Beasts' instruction. 407 412 421

• Fights the Bowel Hunter long enough to protect Felt and Rom despite fear and mounting wounds. 407 408
• Defeats Julius through Shadow Clones, strategy, and a threatened Rasengan. 423
• Fends off demonic beasts while evacuating unconscious children with Rem and Ram. 418
• Controls Meili's magical beast against her during the village attack. 436

Equipment / Weapons / Items

• Black guard uniform — Worn while accompanying Emilia to the royal capital. 421
• Nine Tailed Beasts summoning scroll — Yu's joint contract scroll, used to summon all nine Tailed Beasts. 416 418
• Black dragon token — Given by Yu; when infused with chakra at three in the morning, it opens a path to the Underworld Court. 453 454
• Type 54 machine gun — An Empire-developed firearm Subaru enthusiastically maintains while traveling by aircraft. 447

Relationships

• Uchiha Yu — Master and mentor. Yu grants Subaru power, trains him harshly, and insists he become self-reliant rather than dependent on his master. 404 411 421
• Emilia — Subaru's beloved and the person he is determined to protect. Her early kindness gives him purpose, though his impulsiveness strains their relationship during the royal selection. 409 425 431
• Puck — Emilia's spirit familiar and Subaru's ally against the Bowel Hunter; Puck later kills Subaru after Emilia's death, triggering another reset. 407 430
• Felt — Initially clashes with Subaru over Emilia's insignia. Subaru protects Felt and Rom during the Bowel Hunter's attack. 406 407
• Reinhard — City guard and powerful ally who rescues Subaru from thugs and later acknowledges the Bowel Hunter's danger. 405 408
• Rem and Ram — Companions in the demon-beast forest investigation. Subaru fights beside them and later protects Ram from Roswaal. 418 439
• Nine Tailed Beasts — Summoned allies and later Subaru's practical-combat instructors; they recognize Yu as their master. 418 421
• Julius Juukulius — Rival knight whom Subaru defeats in a training match; later travels with Subaru after the White Whale's defeat. 423 431
• Crusch Karsten — Royal candidate who cooperates with Subaru against the White Whale and agrees to support Emilia after witnessing his strength. 430 431
• Kenichi and Naoko Natsuki — Subaru's deceased parents, reunited with him in the Underworld Court; they had been recruited into its Merits Office because of their merits in life. 454 455

Story Role / Major Arcs

Taking Yu as Master

Subaru meets Yu after a Return by Death loop and becomes his disciple. He guides Yu through events he remembers from previous timelines, seeks Reinhard's help against thugs, retrieves Emilia's insignia, and confronts the Bowel Hunter. Yu temporarily possesses Subaru to finish the battle, resulting in Subaru's first kill. 404 405 406 407 408

Roswaal Manor Training

Subaru becomes Emilia's guard and undergoes Yu's “devil training.” He gains Iron Body, chakra training, Shadow Clones, and the ability to summon the Nine Tailed Beasts, then receives practical instruction from the beasts themselves. 410 411 412 414 416 418 421

Royal Capital and White Whale

Subaru defeats Julius in a spar, is briefly appointed to the knight order, and is expelled after his uncontrolled defense of Emilia disrupts the royal selection. After resolving to correct his mistakes, he suffers further deaths, awakens the Mangekyo Sharingan, and destroys the White Whale with Susanoo. 423 425 426 427 430 431

Witch Cult and Sanctuary

Subaru uses pain manipulation to kill Petelgeuse, investigates Meili's suspicious behavior, saves the village from demon beasts, and confronts Roswaal's manipulation of Emilia. In the Sanctuary, he refuses to become a pawn for the witches' desired perfect ending. 432 434 436 439 441

Reunion with His Parents

Seeking his parents, Subaru receives a token from Yu and brings Emilia through the Underworld Court to meet Kenichi and Naoko Natsuki. He reunites with them emotionally and introduces Emilia as his girlfriend. 453 454 455

Trivia

• Subaru's chakra test reveals five affinities. 414
• He calls Emilia “Emilia-tan.” 421 447
• He is highly enthusiastic about Empire technology and considers piloting an Empire mech “a man's romance.” 447
• Yu considers Subaru's strength of heart exceptional because he continues pursuing his goal despite dying again and again. 453