I Became a Genius Swordsman in the Pretty Girl Game - Chapter 41

I exist in the darkness, disappear under the bright light, and will eventually devour the sun and turn into the shadow of all things… Known by people as the indescribable terror of darkness; the king of shadows; the dark day; the existence of the shadow of the world , is still just a somewhat special high school student, facing a weird death game…

- Description from novelbuddy

This is the story of Kir, who has to thwart the will of Heaven, Hell, and his parents in order to survive, protect the people he loves, and achieve happiness.He just has to make it through life at a magical academy, avoid dying, and survive to find his birth mother, the lost Daughter of Heaven. Or be forced to take his place at the side of his father, a Duke of Hell bent on destroying the way things are.It's a lot to handle for a quiet, brooding angel boy.Fortunately, he has company. A succubus, a foxkin girl, and a half-angel boy to start. And Kir has his own secret: this isn't his first go at life.

It’s a story about a man who got transported into a novel and possessed a slum boy. He met a noble girl and served her as a butler for 13 Years. Now the girl has already fallen from her noble life and lives in an abandoned mansion with paralyzed legs. Why did she become like that? Of course because she is the villainess in the novel.

Insane. Traitor. Terrorist.