Our Housekeeper Is a Guinea Pig

After looking for part-time work, Mei finds a job as a live-in housekeeper that pays pretty good wages! However, it requires that she live under the same roof as three hot brothers: a cool, sadistic eldest brother, a gentle middle brother, and a younger brother whom she just wants to protect... at first, work goes well, but then all of a sudden the middle brother transforms into a sadistic beast and shoves her down! "Noo... I wanted my first time to be with someone I loved!" Lying on a cold hard floor, he forces her open, and to her surprise, her crotch starts to feel warm and gets super goopy! It's supposed to hurt and feel sad... so then why does she feel so good? Soon, the other brothers start to reach out to her...