Ume-chan harbours a huge crush on Isezaki-kun, a boy in her class. She spends a lot of her time writing about him in her notebook, and is content with her unrequited love… since Isezaki already has a kind and pretty girlfriend. One day, however, Isezaki asks Ume-chan if he can borrow her notes. To her horror, she realizes belatedly that she’s given him the wrong book! By the time she finds him, he is already reading the contents of her secret notebook. However, not only is Isezaki extremely nice about it, he even offers to be friends. But when the news that Isezaki has broken up with his girlfriend comes around, Ume-chan begins to think that this could be her big chance.