Game of Divine Thrones - Chapter 125: Memory Garden 2

I killed the protagonist.Yeah. He was a real son of a bitch.Noah didn’t just stumble into this mess. He walked straight in—grinning, sword in hand.One day, he wakes up inside his favorite game… as a throwaway side character no one remembers. A complete nobody. But when he figures out who the so-called “main character” is?Some smug, self-righteous psycho.So yeah—he killed him. No regrets.Story over, right?Not exactly.Because this world? It’s got one more player.“WHAT THE FUCK IS GOING ON!?”Now the story’s off the rails, the world’s gone completely off-script, and Noah’s got a new goal:Steal the hero’s spot. Rewrite the plot. Find out who the hell this other player is. And maybe—just maybe—make this damn story fun for once.

The old man pointed to the flower-like woman and said, “Call her mother from now on.” He then pointed to a flower-bud-like girl and said, “This is your sister.”

My younger sister was not cute.

She was arrogant, taciturn and weird, but she knew how to please our parents.

She was two-faced and deceitful, but it seemed like she only treated me that way.

I cared for her, tried to please her as much as I can, but she still disliked me.

Until one day, I found out her secret, our relationship began to get a little bit weird…

- Description from Novelupdates

Eren Idril died as an old, decrepit, and piss-poor adventurer by the maws of a D-Rank monster. He had a lot of unfulfilled dreams and desires that couldn't see the light of the day after the light in his own eyes died down.

But fortunately for him and unfortunately for the world, that wasn't his end. Eren was somehow dived back in time when he was a mere teen, attending Lionheart Academy for adventurers.

When life gives him a second chance, Eren decides to exploit it to its fullest. Experience his vile deeds as he partakes in them without feeling the slightest bit of hesitation.

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.