18+ Netorare Jukubo Natsuko: Wakai Otoko to no Hentai Sex ni Hamatta Hontou wa Dosukebe Datta Okaasan

Him and his mother lived in a two-person apartment.
Everything was fine, they weren't rich but it was comfortable.
His father had died when he was young, leaving his mother to
raise him. She had her own aspirations, but always put
him first.

Elegant, tender and generous. Very beautiful. He was proud of his mother.
She was his and his alone... or so he thought...

Little by little, their happy life began to crumble...

It's all the fault of a classmate he hates... Kazuya Eguchi.

He was shameless, crass, violent...
Everything that was his, everything he cared about, he destroyed...
That son of a bitch never thought about anyone but himself...
He treated women like disposable sex objects...

The most unforgivable thing is he did it with his mom...

(Source: dlsite, edited)