幼馴染みよりもエロいモブ子との放課後エッチ ～ボクはクラスの地味子に恋をした～

Hiroto Yamagami is a very ordinary and normal student. His childhood friend is a beautiful and popular girl named Aoi Hinasaki.

Aoi has a crush on Hiroto, but he is unaware of it and continues this one-sided love affair with her.

One day, Hiroto sees a girl masturbating in an empty classroom. She is so plain that he doesn't even know her name, but she is Ayumi Sonoda.

She climaxed while stifling her voice and looked up at the ceiling with an ecstatic expression. Seeing her like that, Hiroto felt his first emotion. It was his first love...

[From official site]