Based on the erotic game by Atelier Kaguya Honky-Tonk Pumpkin.

The protagonist, a student, moves into a share house that offers discounted rent in exchange for monitoring a famous bath manufacturer's products. He had thought he didn't get the opportunity, but to his surprise, he's accepted at the last minute. After moving in, he realizes that all the other residents are female upperclassmen from the same school. It's time for some heart-pounding, bath-filled, crazy student life with those ladies!