はやく大人になりなさい。•

Hayaku Otona ni Narinasai.

Nao is a second-year high school student who thinks that nothing good comes from adults, and wants to stay a child forever. But thanks to Mikasa, her handsome biology teacher who's shrouded in mystery, she starts to learn more and more about the world?! How far will today's lesson go? (Source: Hakusensha, translated)