Sang-eun needs to settle a contract with Hae-jin. After some quarreling, Ji-ho's day is Mon, Wed, and Fri and Hae-jin on Tues, Thur, and Sat. And the alternate day marriage begins. Meanwhile, Sang-eun and Ji-ho prepare a housewarming party for his work. While decorating the house they develop feelings. At the housewarming party, Sang-eun drinks too much and gets a serious blackout the next day...