Akira Inugami, a Japanese-American teenager, is the last known descendant of a werewolf bloodline until the emergence of another werewolf, Akira Jin. Born to a werewolf mother and human father, he was orphaned young when masked assailants killed his parents in Alaska. Surviving in the wilderness with a gray wolf pack that accepted him, he was later discovered and sent to live with his aunt. This trauma forged his conviction of being cursed with perpetual misfortune, a belief solidified by psychic Madame Zora's prediction that his life would bring catastrophic bad luck to others.

He possesses a mature appearance featuring messy black hair (which later turns permanently white from overusing his powers), brown eyes, pointy ears, and a tall, slender yet toned build. His werewolf form retains his intelligence and speech while displaying lupine features. Key abilities include transformation linked to lunar cycles, granting superhuman strength, speed, agility, reflexes, and near-invulnerability during full moons. He heals rapidly, regenerating tissue almost instantly in human form. During new moons, his powers wane near human levels, though he can briefly manifest a golden energy enhancing durability and combat prowess for about one hour. His blood carries transformative properties, as seen when a transfusion turned another into a monstrous "Were-Ogre".

His personality blends isolationism, cynicism toward humanity, and deadpan sarcasm, rooted in the belief his presence causes disaster. He initially avoids deep connections to shield others, drifting as an ineffectual loner. This changes after saving homeroom teacher Akiko Aoshika from assailants. Despite resisting emotional bonds, he develops romantic feelings for her, echoing his parents' dynamic (his human father was his werewolf mother's professor). Aoshika becomes his moral anchor and primary motivation, yet their bond draws relentless persecution from yakuza heir Dou Haguro, obsessed with proving himself a greater monster.

Haguro escalates the conflict by kidnapping and orchestrating the gang rape of Aoshika to torment Inugami psychologically. This culminates in a climactic confrontation where Inugami, severely wounded and weakened during a new moon, pushes beyond his limits to rescue her. Expending immense energy—visibly symbolized by his hair turning permanently white—he defeats Haguro, resulting in his apparent death. Authorities recover his body. Believing him dead, Aoshika attempts suicide before resolving to honor his memory by living among wolves in Alaska. Months later, however, Inugami resurfaces as a captive test subject of the clandestine organization Phoenix Organ; his regenerative abilities facilitated revival. Though physically diminished, missing an arm and fingers, he retains fragmented memories of promising Aoshika a life in Alaska. From confinement, he emits a howl sensed by Aoshika and her wolf companions across the distance.