Another Wife.

Jeong Hoon broke up with his first love Seo Yeong due to opposition from his parents. He has no choice but to marry Mi Na, whom her parents introduced, and Seo Yeong commits suicide because she cannot overcome the pain of separation. Although a lot of time has passed, Jeong Hoon tries to forget Seo Yeong and falls into the illusion that he is living with Seo Yeong, who died while struggling. Mi Na, who finds it hard to stand Jeong Hoon's behavior, seduces Jae Hee, a courier, to show Jeong Hoon, and commits an affair.