Kochou serves as a kunoichi under antagonist Muhousai, operating within a covert unit of female ninjas entrusted with safeguarding portions of a treasure map inked onto their skin. The encoded fragments materialize exclusively during moments of climax, a physiological trigger integral to protagonist Matagoro Yoshimura’s quest. True to her name’s entomological inspiration, she wields the metamorphic ability to shift into a butterfly. While her combat techniques employ a traditional ninja arsenal—shuriken, kunai, and blades—she distinguishes herself as the sole operative depicted wielding these tools actively in skirmishes.

Her arc concludes abruptly when Matagoro defeats and kills her during a confrontation. Muhousai coldly cites her demise as evidence of the protagonist’s rising lethality yet dismisses her loss with clinical detachment, underscoring the expendable status of his subordinates. Kochou’s involvement remains confined to the treasure hunt’s opening stages, her background, motivations, and interpersonal dynamics unexplored beyond her unwavering service to Muhousai. Official narratives prioritize her tactical purpose within the mission’s premise, offering no elaboration on her origins or internal growth.