Episode 4 (E04)

Fushihara and Yuurei-chan have taken a black cat named "Myako" in from the rain. But it looks like Myako isn't just any ordinary black cat. To their surprise, Myako is actually a bakeneko, a ghost cat from Japanese folklore that is able to transform into a human. Myako takes on her human form, so that she may repay Fushihara for her kindness, and Fushihara gladly welcomes her into her home. Later, when Fushihara is doing overtime at the office, Yuurei-chan and Myako begin fighting over who gets to help her with her work... (Crunchyroll)