From the moment the introverted upperclassman crossed paths with Nagatoro Hayase and her friends in the library, his life turned upside down. Seeing the flustered reactions of the upperclassman when being teased by other girls, Nagatoro found it amusing and started to continuously toy with him. In fact, Nagatoro's teasing was her way of expressing affection towards him, which he failed to recognize. However, as their trust and fondness for each other gradually grew, it slowly pushed both of them past the line of being just friends.