Su-In

A third year senior, Su-In has, for a long time, had her eye on Se-joon. Finally, Se-joon agrees to date her and think of her as his girlfriend much to his sister's, Se-wa, chagrin. Su-In finds herself in a lot of pressure when she tries balancing school, club activities, her family's expectations for her future studies at a good university and her struggles with her relationship with the twins. After realizing that Se-Joon doesn't really love her, she leaves him.