Based on the erotic game by POISON.

Ryuusuke is a college student working part-time as a private tutor. However, both his student Azusa and her mother, Sakiko, dislike him because he is an F-ranked student with bad looks, and he is stressed out everyday. Then, Ryuusuke is given a "hypnosis device" by Nonomiya, an alumnus of the university. It is an earring-shaped device and remote control that uses special radio waves to control the wearer at will. He immediately gives Azusa the earrings and puts her into a hypnotic state......!!

(Source: Parabook, translated)