DxD: Matsuda? - Chapter 89: Dogeza House?

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.

Luo Zheng is at the bottom of the Luo Clan hierarchy, despite his family being the founders of a power refining technique that could instantly defeat any opponent.

This story is about a rookie researcher, who was forcefully dragged away from his restful life, compelled into facing various killers and zombies, always having to risk his life at the brink of death, and finally becoming an advanced researcher that is acclaimed by all. And throughout his adventure, he met an alluring(?) killing machine, who he started to have fantasies on after they had an accidental kiss…

Xiao Yan: Did I fall for him? But he’s a man!

Maya: Who knows…. maybe it’s the other way round?

- Description from Novelupdates

I closed my eyes and let out a long, shuddering breath. The needle slipped through my numb fingers and clattered onto the rough pavement. Nothingness swirled around me, bringing the first peace I'd felt in my short, miserable life. No one would miss me, and if any did...? Well, there was always someone else to beat or rape. They'd move on quickly.But then...gods? Since when did nothingness have so many gods?Chosen by the goddess of Fate, I'm thrust into a world of magic and wonder alongside nine other heroes. A world where the gods reign supreme, and evil is vanquished before it can spread its blight.Can such a place truly exist? Could life really be worth living?I've heard that the brightest lights cast the longest shadows, but my life has been nothing but darkness. Perhaps this new world will be the chance I need to find the light, to see the other side.