The harder you try, the more miserable your life becomes

Jeon Yeo-ju, the school's representative problem child, also has unavoidable circumstances and a pain that no one can compare to. She always pretends to be cheerful, and is so strong that crying is unimaginable. However, after meeting her twin brother Jeon Jung-kook, the only person who believed in her, and six close friends, she overcomes her pain and resolves to become happier than anyone else.