A female college student upstairs who likes big things! Instead of her boyfriend, she became addicted to sex with the owner downstairs.
Min-soo and Joo-hee are newlyweds and should be on their honeymoon, but they are worried because the interest rate on their loans has risen recently. The couple decided to offer the upper floor of their house for rent to help pay the loan interest. After a while, Soo-jin, a college student, came to become their tenant upstairs. While Min-soo is looking for batteries for the remote control, he accidentally sees Soo-jin masturbating in her shower room, and Min-soo develops a sexual attraction to her. The location of Soo-jin’s school is along the way to Min-soo’s company, so he drives her, which helps the two get to know each other. Later, Min-soo is the one masturbating in his room while fantasizing about Soo-jin, but this time he is caught by Soo-jin, who is surprised to see Min-soo’s stuff. On the other hand, Dae-cheol, Soo-jin’s lover, comes to pick up Soo-jin’s school assignments when he sees Joo-hee doing her home workout. He becomes sexually attracted to Joo-hee as she teaches him how to stretch.
The conflicting sexual desires of a college couple and a newlywed couple begins.