TV-Series
Description
Koichi Hayase starts as a bullied junior high student who escapes through heroic daydreams. His life shatters during a class trip when the Machina robot Linebarrel crashes near him, causing his death. Resurrected by nanomachines (D-S.O.I.L.) after Emi Kizaki, Linebarrel's pilot, pleads for his life, he becomes a "Factor"—a human bound to a Machina's life force—gaining superhuman strength. This power fuels his arrogance. He adopts a domineering persona, battles bullies to become the top delinquent, and treats Linebarrel as a tool for personal glory. His reckless early fights cause heavy collateral damage, straining ties with childhood friends Hideaki Yajima and Risako Ishigami.
A turning point comes when Yajima dies protecting others, forcing Koichi to confront his irresponsibility. Humbling defeats, particularly by skilled pilot Reiji Moritsugu, catalyze his maturity. He evolves into a more serious protector, though retains streaks of recklessness and vanity. His relationship with Emi Kizaki begins antagonistically due to his abrasiveness but deepens as he vows to protect her. Romantic tension simmers, though he struggles to voice his feelings. He later discovers Emi is a dimension-traveler connected to Linebarrel's origins and the sister of antagonist Katou Hisataka.
As Linebarrel's Factor, Koichi pilots this premier Machina. Its arsenal features dual katanas and the "Executor" beam cannon, capable of generating kilometer-long energy blades. Linebarrel can shift into "Mode-B" (anime) or "Override" (manga), a jet-black form granting teleportation and amplified power at severe physical cost. Initially, Koichi relies solely on Linebarrel's brute force, lacking the technical skill of rivals like Moritsugu. Defeats and battles, especially against the entity Amagatsu, hone his abilities, unlocking more of Linebarrel's potential.
Years later, standing 183 cm tall, he mentors younger pilots like Miu Kujo, though this is disrupted during a timeskip. The narrative reveals humanity was nearly wiped out centuries earlier by Machina searching for purpose; factions like the "Human-Machina" now aim to remake humanity. Koichi confronts this threat, facing foes such as Deus Ex Machina and Maxi Oba. His journey culminates in rejecting predetermined roles, embracing agency with the conviction: "It’s not 'what I should do,' it’s 'what I want to do.'" Koichi transforms from a self-absorbed youth into a protector driven by loyalty and sacrifice, his heroism rebuilt yet still marked by flaws.
A turning point comes when Yajima dies protecting others, forcing Koichi to confront his irresponsibility. Humbling defeats, particularly by skilled pilot Reiji Moritsugu, catalyze his maturity. He evolves into a more serious protector, though retains streaks of recklessness and vanity. His relationship with Emi Kizaki begins antagonistically due to his abrasiveness but deepens as he vows to protect her. Romantic tension simmers, though he struggles to voice his feelings. He later discovers Emi is a dimension-traveler connected to Linebarrel's origins and the sister of antagonist Katou Hisataka.
As Linebarrel's Factor, Koichi pilots this premier Machina. Its arsenal features dual katanas and the "Executor" beam cannon, capable of generating kilometer-long energy blades. Linebarrel can shift into "Mode-B" (anime) or "Override" (manga), a jet-black form granting teleportation and amplified power at severe physical cost. Initially, Koichi relies solely on Linebarrel's brute force, lacking the technical skill of rivals like Moritsugu. Defeats and battles, especially against the entity Amagatsu, hone his abilities, unlocking more of Linebarrel's potential.
Years later, standing 183 cm tall, he mentors younger pilots like Miu Kujo, though this is disrupted during a timeskip. The narrative reveals humanity was nearly wiped out centuries earlier by Machina searching for purpose; factions like the "Human-Machina" now aim to remake humanity. Koichi confronts this threat, facing foes such as Deus Ex Machina and Maxi Oba. His journey culminates in rejecting predetermined roles, embracing agency with the conviction: "It’s not 'what I should do,' it’s 'what I want to do.'" Koichi transforms from a self-absorbed youth into a protector driven by loyalty and sacrifice, his heroism rebuilt yet still marked by flaws.