Yeon-joo and Chan-hyeok loved each other like any other couple at first. However, Chan-hyeok became cold to Yeon-joo, and after fighting, Yeon-joo leaves the house where they lived together. Yeon-joo walked to the place of memories while crying. She recalls her first meeting with Chan-hyeok and tries to forget him by drinking. Chan-hyeok calls Min-ah whom Yeon-joo had met in secret, and Min-ah knows Yeon-joo as Chanhyuk's older sister...
