"Hey, shall we kiss?" There could not be a bunny girl inhabiting a library. Azusagawa Sakuta faced a scene that toppled common sense—he encountered a bunny girl, and she is nowhere a normal bunny girl. She is Sakurajima Mai, a student studying at the same school as Sakuta and a retired yet renowned actress. It was said that starting from a few days ago, those around her could no longer see her anymore, and she came to the library just to confirm this. Is this related to the hit topic on the internet, the unimaginable phenomenon known as "the puberty syndrome"? Sakuta, wanting to know the reasons behind and get closer to Mai, decided to solve the puzzle. However, the situation then developed in an unexpected way—? (Source: LightKingdom)