Despite being sworn enemies, Hana takes it upon herself to mentor Haba, a newcomer to the world of education, on the intricacies of being a transfer student. She also warns Haba about her behavior, which mirrors that of a rebellious second-year junior high school student. Surprisingly, Haba discovers that Hana, despite her yearning for friendship, is also friendless. In a bold declaration, Haba names herself 'Friend No. 1'. Just as they agree to coexist peacefully, a mysterious new transfer student arrives, setting the stage for an unexpected twist in their intertwined destinies...