One day, shy high-school boy Kazuo Matsui comes across an old cardboard box with a litter of stray kittens inside. It is there he has a chance encounter with Kitahara, an antisocial elementary school student. Even though he seems unapproachable, Kazuo finds the boy intriguing. He adopts a kitten and hatches a plan to become friends with Kitahara. Soon, Kazuo finds the simple friendship transforming into something deeper. Is it love? Does Kitahara return Kazuo's feelings?