MTL - Supreme Demon - Chapter 3271 Final Four!

Based on the popular Vocaloid series, by HoneyWorks, called “Kokuhoku Yokou Renshuu (Confession Rehearsal)“:

Natsuki, a third-year at Sakuragaoka High School, who holds unrequited feelings for her childhood friend, Yuu, who’s in the Film Club. However, instead of being honest about her feelings, she makes him be her confession “rehearsal” partner. Unable to say her true feelings, things start to get complicated when Miou and Akari, who are also in the Art Club, get involved! Will she ever be able to confess for real!?

Hakuto's life changes forever when his father Shin— a man with highly questionable morals—marries Kagura Kurotsuki, the CEO of a multinational company, and they move into her luxurious mansion.There, he meets the alluring daughters of his new stepmother: the seductive Yuzu—who doesn't hesitate to tease both her new stepbrother and her stepfather in ways that are... rather bold—and Rika, more introverted and irritable, yet just as sensual.But nothing is truly as it seems...Kagura is a succubus, but Rika and Yuzu are different.They were born from a demon and a vampire—something that shouldn’t be exsiste.Because of that, demons, vampires, even humans want them.But Hakuto won’t allow it.He’ll never let anyone hurt his beloved stepsisters.

The simulation is over, and the entry is obtained: a showdown!

Looking at this entry, Zhao Meng was stunned.

“How should this term be used?”

“Hey! Here’s a wounded fox!”

…

A few years later, a woman who looked like a fairy appeared in front of him, and said:

“My lord, I’m here to repay my favor!”

This book is also called “Starting from Transforming Monsters”

- Description from novelbuddy