Takumi Tsuzuki is an orphan who spends his days with his childhood friend Fumino Serizawa at the cafe "Stray Cats" and with his friends, in the Umenomori academy. One day, his older stepsister Otome brings home a strange girl named Nozomi Kiriya to live with them. And when his other friend - Chise Umenomori starts a "Stray Cats" club that helps people, Takumi's life is filled with new activities.