Koizumi is a girl who is always made fun of because she is tall, and Ootani is a boy who is always made fun of because he’s short. The two are very alike in personality and interests, and bicker to the point where they’re like a comedy duo. The two of them end up in summer school – Koizumi because she fell asleep and screamed aloud during an assembly, and Ootani because he failed.
The day before summer school Koizumi tells her friends, Nobu-chan and Chihara, that she’d be able to better get through the experience if she had someone she liked. Lo and behold, the next day in class a boy named Suzuki from another class is also in summer school and Koizumi instantly gets a crush on him. Ootani realizes this immediately and gets “evil” plans.
After class, Ootani tells Koizumi that he knows she likes Suzuki, and he’ll help her get together with him if she helps him get together with Chihara, and she agrees. Later on, the four of them, plus Nobu-chan and her boyfriend Nakao-kun, go to the pool. Things are going well, if a bit awkward, as Ootani and Koizumi get to know their interests. When Nobu and Nakao go on the waterslide, Ootani and Koizumi want to go also, but Suzuki and Chihara are both afraid, so they go on it together. When they come back, Suzuki has disappeared and Koizumi panics, but it turns out he was buying drinks.
As everyone leaves, Koizumi tells Ootani she’s worried because Suzuki and Chihara went home together. He tells her not to worry. However, the next day Ootani is crushed because Chihara doesn’t think of him as a boy because he’s short, and likewise for Kotani – because she’s tall, Suzuki doesn’t see her as a girl. The two help each other out and decide to invite their interests to the summer festival.
Ootani initially blushes when Koizumi shows up in a yukata, but plays it off as thinking she was someone else. When Chihara and Suzuki show up together, it becomes apparent to Koizumi and Ootani that the two like each other, so they give up and go off by themselves. They both have a lot of fun, and Koizumi later ends up blushing because of Ootani.
The next day at school, the two are back to fighting again, and initiate a contest to see who can get a significant other first.