Katsumi Ebata, a 16-year-old first-year high school student, plunges into a perilous conflict between ancient Japanese clans after chasing his romantic interest, Sakura Hasegawa, into a mystifying parallel realm. This dimension seamlessly blends the courtly elegance of the Heian period and the warrior ethos of the Kamakura era with neon-lit modern districts akin to Shinjuku.

His uncanny likeness to the slain warlord Minamoto no Yoritomo thrusts him into a desperate bid to conceal the leader’s death, as the Minamoto clan enlists him as a decoy to outmaneuver the rival Heike. Propelled into political machinations and battlefield chaos within the Kamakura shogunate, Katsumi walks a razor’s edge, torn between personal desires and the burdens of borrowed authority.

The story traces his precarious dance across timelines, juggling lethal power struggles in the feudal realm with fragile ties to his ordinary world. His bond with Sakura anchors his choices, though their evolving dynamic remains largely unexplored. A cryptic talking animal companion shadows his journey, though the creature’s purpose and importance stay undefined.

Sources reveal nothing of his origins prior to becoming Yoritomo’s stand-in, his familial ties, or his ultimate destiny once the clash of clans concludes.