Blood Shaper - Chapter 45Book 4:

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.

Lin Yi failed the college entrance exams and chose a diploma mill university.

And as deserving of a diploma mill university, the first line of the admission letter read:

- Description from Novelupdates

“She is the one who forced me to marry her, she is also the one who pushed away ShuangAi from me, she threatened my family with her family power and all these years, she did everything to subdue me...that evil woman MuTan“

I was the one who boosted your rank. Yet you stabbed me in the back? Fine. Goodbye. I’m taking it back. You’re finished now. Thanks to you, I now have an abundance of skill points for a prosperous hunter life. But… after spending some of those points, the S-Rank is starting to get obsessed with me…?