Giyu Tomioka serves as the Water Hashira in the Demon Slayer Corps, possessing a lean, muscular build and typically maintaining a stoic expression. His sharp, moderately large blue eyes and uneven black hair, later worn shorter at neck-length, are distinctive features, often tied in a low ponytail. He wears the standard black Demon Slayer uniform beneath a unique two-patterned haori: one half solid crimson red, once belonging to his deceased sister Tsutako, and the other half geometrically patterned in green, orange, and yellow, formerly owned by his late friend Sabito. Following the battle against Muzan Kibutsuji, he loses his right arm. Orphaned young, Giyu was raised by his older sister Tsutako. Demons attacked their home on her wedding day; Tsutako sacrificed herself to protect him, instructing him to flee. After others dismissed his account as mental illness, he ran away, nearly perishing on a mountain before Sabito found him. Sabito took him to Sakonji Urokodaki, a former Water Hashira. Training alongside Sabito, Giyu displayed a cheerful disposition. Both participated in Final Selection on Mount Fujikasane. Giyu suffered an early injury and Sabito saved him, then defeated nearly all demons on the mountain. Sabito perished protecting others, leaving Giyu as the sole survivor. This event triggered severe survivor’s guilt and marked the onset of his withdrawn personality. Giyu’s personality is defined by emotional reserve and a strong sense of justice. He speaks minimally and maintains distance from others, partly due to perceptions of arrogance from fellow Hashira like Sanemi Shinazugawa and Obanai Iguro. Beneath his aloofness lies deep-seated insecurity; he grapples with his worthiness as a Hashira, believing Sabito deserved the role more. This inferiority complex leads him to initially refuse participation in Hashira Training. Despite his stoicism, he demonstrates fierce protectiveness toward comrades. He violates the Demon Slayer Corps’ code by sparing Nezuko Kamado after witnessing her defend her human brother, Tanjiro. He later vows seppuku if Nezuko harms humans and shields her from other Hashira. His composure fractures only when allies face peril, such as during Akaza’s assault on Tanjiro or upon learning of Shinobu Kocho’s death. Giyu first encounters Tanjiro and Nezuko during a demon attack. After subduing Nezuko and observing her refusal to consume humans, he directs Tanjiro to Urokodaki for training. He later aids Tanjiro during battles on Mount Natagumo, defeating the Father Spider Demon and Lower Rank Five Rui. He physically intervenes when Shinobu attempts to kill Nezuko. His relationship with Tanjiro becomes pivotal; Tanjiro’s unwavering resolve helps Giyu confront his survivor’s guilt. Giyu gradually accepts that living honorably, rather than dwelling in guilt, honors Sabito’s and Tsutako’s sacrifices. Post-battle against Muzan, he shows increased openness, smiling during interactions with Tanjiro, Nezuko, and Sanemi. As a Hashira, Giyu ranks among the Corps’ most formidable combatants. He masters Water Breathing, developing an eleventh form, Dead Calm, which nullifies incoming attacks. Key feats include effortlessly defeating Lower Rank demons, holding his own against Upper Rank Three Akaza—who acknowledged his refined swordsmanship as unparalleled among Water Hashira in 50 years—and contributing significantly to Muzan’s defeat despite losing an arm. During the battle against Akaza, he awakens a Demon Slayer Mark resembling water on his left cheek, enhancing his speed and precision. His tactical intellect includes accurately analyzing opponents mid-battle and employing cauterization to manage severe injuries. He temporarily wields a crimson-red Nichirin blade during the Muzan confrontation, hindering demon regeneration. Giyu’s character arc concludes with him overcoming survivor’s guilt through Tanjiro’s influence. After Muzan’s defeat, he adopts a simpler wardrobe and shorter hair, reflecting his emotional resolution. He maintains connections with allies like Tengen Uzui and Sanemi, signaling mutual respect forged through shared battles.