In a country where all races of human and creature live together, love is blossoming as people don't worry about each other's quirks or appearances. Among them is a clumsy dullahan who's head over heels about her track star boyfriend, a confused boy who questions how to talk to his mermaid crush, and a cute centaur wondering how to confess to her childhood friend.

Everyone seems to be catching the love bug except for Setsuka, an icy oni who usually gives humans the cold shoulder. That changes when a determined, kind classmate named Eiji confesses his love to her, lighting a small spark in her chest. With advice from her monstrous friends and equally lovestruck sister, Setsuka's cold heart might turn red hot soon enough!