My Girlfriend's Ex Roommate

Sehyun’s first crush left her heartbroken, but she finds true love in college, where she meets her first girlfriend, Sunwoo. The couple happily share an apartment until Sunwoo is forced to move away after graduation. Sehyun takes in a new roommate, Gina, who turns out to be… Sunwoo’s ex? Will Sehyun and Sunwoo’s relationship survive Gina’s attempts to win Sunwoo back?