Still 17 EP 9

Woo Jin's older sister and Chan's mother, Gong Hyun Jung, surprises everyone by dropping by Woo Jin's place. Worried that his mom would get mad for allowing a stranger to live at their place, the boys decide to lie to her and say that Seo Ri is their housekeeper. However, Seo Ri feels very uncomfortable about lying and tries her best not to be seen by her.