Yoru wa Neko to Issho (Nights with a Cat)

Synopsis

Fuuta-kun has never owned a cat before, but his younger sister, Pii-chan, moves into his house with the round gray cat Kyuruga. Inexperienced with cats, Fuuta-kun has no idea what to expect, and each night after he returns home is marked by odd and endearing surprises from his new pet. [Written by MAL Rewrite]