Min-woo lives separately with his younger brother’s friend Hae-ri because of household clashes. The younger sister, Su-mi’s opposition is the most severe. Su-mi, who became a family member through remarriage of her parents, still has a crush on her older brother Min-woo alone. Su-mi is carrying out a dangerous plan to break him up with Hae-ri.
Min-ho, who is newly married, works for a small business. But all of his colleagues have been promoted but he is the only one left as a manager. For Min-ho, there suddenly had an opportunity. The president of the company moves right next door, had meal with him and his wife, and Min-ho gets closer to the boss. The drinking party gets hot and Min-ho gets drunk, so the boss seduces Yu-mi with Min-ho's promotion as bait.
