Son's Girlfriend, Daddy's Girlfriend Collection

Dong-gook, who is thinking of remarrying, introduces his stepmother Kyeong-sook to his son Jin-yeong. At the family gathering, Jin-yeong is surprised to see his stepmother's younger brother Hyeon-sook who was his one-night stand just a few days ago! Jin-yeong and his stepmother is lying down, drunk. Meanwhile, there is a strange atmosphere between Dong-gook and Hyeon-sook, who were drinking alone, and at that moment Jin-yeong's girlfriend Joo-yeon appears drunk.

Jeong-goo is in a relationship with his son's girlfriend, Mi-hee. Mi-hee feels guilty and breaks up with Yeong-jin, and Yeong-jin who is struggling because of it, got in a relationship with Joo-eun. Yeong-jin's ex-wife, Yeon-ri meets Jeong-goo by chance and finds out about the whole thing, and Yeon-ri who was curious about Jeong-goo, sleeps with him...