Synopsis：Pretty office lady Yu Xin met handsome Chu Fan the night they both broke up—one for being cheated on and the other for impotence in bed. They decided to go to karaoke for fun, and ended up in a hotel room both drunk, only to be caught for suspected prostitution by police. Fortunately, Zhang Yang, their mutual friend, testified for them and kept them from being taken away. Later, they went to the first-year anniversary of Zhang Yang and his girlfriend, Li Meng. Together, they went on a picnic and put up in a love hotel at night. By some odd chance, the two were arranged in the same room. With feelings for each other, they slept together. They also reached an agreement to never engage in love and thus began their sexual partnership. As time went by, their relationship faced another test.