Rin is a high school girl who adores cats but suffers from a severe allergy that prevents her from being near them. One day, she discovers a weakened cat at a local shrine and, surprised to find she has no allergic reaction to it, decides to take it home. When she falls asleep keeping the cat warm, she wakes up the next morning to find the cat has transformed into Tachibana, her cold and unfriendly classmate, who is naked and equally confused. It turns out that due to a mistake by a god, Tachibana is cursed to turn into a cat only at night. Rin, overjoyed to finally have a cat she can touch, offers him a place to stay, and the two begin a secret cohabitation. The story unfolds as a romantic comedy centered on their daily life together, balancing Rin's caretaking nature with Tachibana's prickly personality, while navigating the supernatural secret that binds them and the growing feelings that develop between the otherwise mismatched classmates. The setting is contemporary Japan, primarily at Rin's home and their school.