The misunderstanding that separates them in junior high never actually gets resolved, and that unfinished thing between them is what the whole show is really about. Futaba spends high school trying to be invisible so no one will hate her, then Tanaka walks back into her life changed in ways she doesn't understand, and watching them actually talk to each other for the first time becomes the most honest romance on screen. This isn't a show about two people falling in love, it's about two people learning they were never as far apart as they thought.
Futaba's strategy is simple: become aggressively unfeminine so her classmates won't resent her looks. In junior high, the other girls shut her out for being cute, and a misunderstanding kept her from telling a boy named Tanaka how she felt before he stopped coming to school. High school is supposed to be her fresh start, a chance to reinvent herself away from that old hurt. Then he walks back in. Same person, different name: Mabuchi Kou. He admits he once felt the same way she did. But he's distant now, guarded in ways that make clear the three years between then and now have changed everything. Futaba finds herself torn between the careful identity she's built, and the friends it protects, and the pull of something unresolved. Can she actually go backward to finish what never started?