Shima is a young cat which doesn't have an owner. For some time, he stays with Hiro (this way, making Fuji jealous), saying that it's "just for the food". Eventually, he too falls in love with Hiro and decides to leave.
After leaving Hiro's place, Shima starts to wander around for food. Due to starvation, he faints and falls into Taki's bag and ends up in his apartment. After meeting with Taki's ex-boyfriend (also named "Shima"), he prays to God to give him speech, so he could tell Taki-san that Shima (the ex) loves him. He wakes up in the morning as a boy. After some time, he falls in love with Taki-san and, due to the similarity of names between him and Shima-san, there will be some misunderstandings.