Kurumizaka Rui♀

A working female student who's a popular nationwide idol attending the same high school as our protagonist. A girl of exceptional beauty, admired by both men and women, and considered to be the perfect idol blessed with many different talents. For those reasons, she doesn't show her weaknesses to anyone, putting lots of pressure on her mind, to the point that it becomes suffocating as a result. By meeting with her ideal master, she will even be able to display her own genuine masochistic-natured self and spend her days having fun as her boyfriend's masochistic pet.

[Adapted from the official description on Getchu]