My Friend's Aunt.

Aeran and Hoseok are in a period of boredom. Jung-woo, a friend and disciple of her husband's nephew, enters the boarding house, and Ae-ran begins to feel lost in the appearance of young and handsome Jeong-woo. Ae-ran and Jung-woo finally have a hot night. The secret love affair continues without Hoseok's attention, and one day, when Jung-woo's girlfriend Hye-mi appears, the four people's strange relationship begins to come to light...