Souta Inui, who has a timid personality, has a peculiar constitution that causes him to take on the form of a dog if "certain conditions'' are met. Ryo Kurose, a childhood friend who always helped Souta whenever he got bullied, will also turn into a cat if the same conditions are met.
The two were separated due to family circumstances when they were young, but reunited several years later.

Souta tells Ryo that he's always loved him, but Ryo doesn't take him seriously at all. Even though Souta declares that it is his turn to protect Ryo, he ends up being saved yet again. People love him when he's a dog, but he wants Ryo to like him as a human too.
Sweet dog x tsundere cat love