With the arrival of Bum-Moo's stepsister, Yun-Ook is even more confused about her feelings for him. Although he wants to be with her, she keeps treating him as just a friend. Then, enter Yun-Ook's ex-boyfriend! And as if matters weren't complicated enough, the stepsister wants Bum-Moo to move out and live someplace else with her! Will these two roommates ever become something more?