Kemonokko Tsuushin The Animation Episode 4

Pokora, a chubby, thick-browed raccoon demi-human, suddenly appears at the protagonist’s house. She is weak to erotic stimuli, and her transformation spell is quickly undone, so he ends up accompanying her in her training,
and attacks her plump body as she transforms into a bunny suit and swimsuit. Thanks to the training, Pokora is now able to withstand it, but her biggest weakness (anal hole) remains…