Hell is All For One

80% of the human population has gained superpowers called "Quirks". Quirks vary widely and can be inherited. Among the Quirk-enhanced individuals, a few of them earn the title of Heroes, who cooperate with authorities in rescue operations and apprehending criminals who abuse their Quirks, commonly known as Villains. But not all men are created equal, and that sentiment definitely applies to one man Y/n L/n.

Born as the second son to the world's strongest villain F/n L/n. But Y/n never met his father, because his older brother Shinsuke L/n had killed him. Shinsuke raised Y/n, until Shinsuke left Y/n at a fancy orphanage. Because there were followers of F/n who wanted to kill the brothers for killing F/n. So Y/n grew up alone, along the way picking up a manga called Demon Lord which was about out a powerful villain called All For One, with the a quirk that has the ability to steal and give quirks to others.

Unfortunately though the men Shinsuke was trying to protect Y/n from found him. And Y/n was killed via poisoning. Even in death Y/n was never at peace, because he was going to be sent to hell to hide the sins F/n has committed in his lifetime. At least he would have, if a well dressed otherworldly being named Fanir stepped in. He gave an offer to Y/n he'll grant all his wishes, in exchange he will defeat Fanir one day. What Y/n wished for the power of his favorite character All For One. The Demon Lord is real, now what adventures await him.