MTL - Marvel: I, Created the Masked Foundation X - Chapter 126

When an S-class elite assassin-raised captain of a special ops suicide squad comes home from a high-stakes Africa mission, he finds himself offered something that could potentially set him up for life- a curious assignment that he could use to finally exit his days of war and slaughter.

Then placed into a high-school setting, Lin Yi is tasked by the chairman of a top-tier multi-billion company with bodyguard duty for non-other than his own daughter, a certain little Miss of said high-school.

His enemies, once ranging from drug lords, mafia bosses, political figures, and national leaders, are soon replaced with spoiled kids who happen to have rich papas and mamas, and Lin Yi finds his intense expertise and high-threat skillset misused, and very underwhelmed…

But he does get a harem cast as diverse as his old enemies, so Lin Yi decides that, for the sake of messing around with girls as an invincible entity in a down-leveled environment, leaving his bloody and death-filled war days behind is something he’d definitely want to strive for.

- Description from Novelupdates

"The boy has no powers," they claimed.

“Go Yohan, you really are a terrible bastard.”“I can’t help it. Bullying is more fun than being bullied.”Despite his outer appearance of a kind model student, Kang Jun was filled to the brim with an inferiority complex.As he advanced into his second year, he grew closer to Go Yohan, who was in the same class as him.“I’ll treat you especially different.”At some point, as if it were only natural, Go Yohan claimed his seat at the very summit of the pyramid inside the school.He, whose second nature seemed to be ignoring and suppressing others, showed interest in Kang Jun.Kang Jun, who was subtly ignored by his friends for being weak, didn’t dislike Go Yohan’s interest, but…Eighteen, the period where one’s pride took the lead and held fear of crossing the line.Kang Jun had to make a choice to survive.A very wise choice.

Dr Dalton Wyatt, a world renowned Scientist and Inventor is transmigrated to the body of a high school student Dalton Wyatt who committed suicide due to unfortunate circumstances and complicated life.