Ye Kai was born with a weak body, and because of his weak body, he couldn't do much but spend his days with his mother and sister.
Like his usual day, he heard a ding voice and got the Unlimited Item Shop System, where he can buy anything.
The first thing Ye Kai buys from his Unlimited Item Shop System is Lust System, to make his fantasy true, where he is having sex with his mother and sisters.
---
The story is slow-paced.
-----
I also wrote novel called I Became Scum in Depressing Game, The Nameless Boy Reincarnated in Novel, and The Adopted Family.