Shougakusei no Himitsu

Overview

There are many firsts when you are a child. The first time your heart pounds fast when you see your childhood friend, when it didn't do so before. The first changes in your body. Friendships and relationships that all too sudden become more complicated. The times when you don't want to talk to anyone, but it feels too hard to bear alone. This is the story of elementary school children. (Source: Elex Media)

Source: AniList