Junpei Kousaka is a high school sophomore who suffers from an allergy to cats, which has led him to despise felines and anything associated with them. Unfortunately for him, he is constantly around cat enthusiasts: his family, his distant childhood friend, and even the girl he has a crush on, Kaede Mizuno.
One day on his way home from school, Junpei casually tries to kick an empty can into a trash bin but fails badly. Instead of landing in the garbage, the can knocks the head off a statue of a cat deity. That very day, he is cursed with the ability to comprehend what cats say. However, he must conceal this curse from everyone, because anyone who learns of it will become more prone to accidents and share the same fate.
With advice from his cat Nyamsus and having no other option, Junpei must now perform one hundred good deeds for cats in order to break the curse. If he fails to accomplish this task, he will transform into a cat, and given his allergy, that would mean certain death for him!