Old friends Yoon-soo, Jong-gyoo, and Jin-gyoo reunite after a long time and share drinks while catching up on each other's lives. Yoon-soo, who is married to Ji-soo, confides that he's been struggling with issues in his sex life with his wife. Jin-gyoo reveals that he broke up with his girlfriend, Mi-kyeong, because their sexual desires didn't align, and he now satisfies his needs at karaoke bars, massage parlors, and similar venues. As the three friends get tipsy, they decide to have a wild night at a room salon. Thanks to the tips he picks up there, Yoon-soo is able to improve his marital sex life. Encouraged by this, his friends begin visiting room salons more frequently.

Bar examiner Yoo-jeong likes sex more than studying. Thanks to the secretive, but erotic tutoring by the teacher her boyfriend introduced to her, Yoo-jeong’s grades shoot up. Yoo-jeong’s mom, Mi-jin, however, feels attracted to her tutor and starts seducing him.

Woo-jin, who is a repeater of college entrance exam, and Taek-sik's friend, Kang-hee come and visit Woo-jin's hometown on a small island. Woo-jin's mom, Hyeon-sook operates a small sashimi restaurant and a bed and breakfast to make a living on the island. Although Hyeon-sook has sex with Bong-seong, she rejects his proposals. One day, Woo-jin is terribly shocked to accidentally see his mom Hyeon-sook and Bong-seong having sex.