Ayame-kun is a reserved, herbivorous college student who prefers quiet study sessions and solitary lunches. The conflict begins when Rika, a boldly carnivorous and socially uninhibited senior from his seminar, decides that his calm demeanor is the perfect challenge for her predatory romantic instincts. The setting is a modern Tokyo university campus, with its libraries, cafeterias, cherry-blossom-lined paths, and the shared off-campus housing where several students live.

The storyline follows Ayame’s gradual, bewildering seduction by Rika, who openly states her intention to “eat him up” in both a playful and literal sense. She invades his personal space, shares bento boxes with aggressive intimacy, and orchestrates study dates that quickly turn into tense, blush-filled encounters. Ayame, initially resistant and embarrassed, begins to notice his own growing appetite for her attention.

Key narrative arcs include the Cultural Festival arc, where Rika volunteers them for a kissing booth and forces Ayame into a maid costume, leading to their first public display of affection. The Rainy Season arc has them trapped overnight in the campus archive, where Rika’s boldness clashes with Ayame’s old-fashioned boundaries, resulting in a confession that reverses their roles. Later, the Home Visit arc introduces Ayame’s traditional family, who misinterpret Rika’s forwardness as rudeness, forcing him to defend her for the first time. The final arc, Graduation and Moving In, sees Ayame transform from passive prey to an active pursuer, deciding to follow Rika to her new job’s city and declaring that he now wants to “devour” her future in return.