The three brothers Han Jun, Hyun Chang, and Seung Tae live in one house. The first, Han Junman, married Jihyun. Hanjun and Jihyun go on a trip to celebrate their first anniversary of marriage. The youngest Hyunchang calls his wife, Yoon-ji, who is a Visa's girlfriend.

Sex Education for the Sister-in-law

In-hee, a skin care specialist and Nam-hyeok met in high school and got married early. Nam-hyeok has inferiority complex from not being getting able to get a job and is tired of the same old life. Feeling a sense of shame, Nam-hyeok goes into a cafe one day and pretends to be the section head of a major company. He visits the place everyday to be comforted by the female owner Joo-yeon. Bong-goo Joo-yeon's little brother who doesn't have a real job and lives off the pocket money she gives him for running her errands. He watches Mi-ae's eating channel and falls for her. Graduate school teaching assistant Ji-hoon maintains a sexual partner relationship with Mi-ae, but she is serious about him. Meanwhile, Ji-hoon follows Mi-ae to the skin care specialist and meets In-hee then falls for her right away...