Sulli is a high school student, she has been in love with Minho for the past two years and she really wishes him to fall in love with her. Sulli had a close relationship with Minho, they were true friends, many people had told them they would look good as a couple, while Sulli would think of it happily Minho would just say a joke about it and annoy Sulli with that.

When Jiyeon entered their highschool she instantly fell in love with Minho and tried to become close to him, when she noticed Sulli was very close to him, Jiyeon started to hate Sulli and turned her into her rival. After meeting Sulli, Jiyeon thought Sulli was a very kind person who wouldn't hurt anyone even if they provoked her so she thought it would be easy to make her give up on Minho. After their second year at highschool finished first she thought she had achieved her objective until they went back to school.