MTL - From the Head Pillar Tanjiro, Take Stock of the Wonderful Nicknames of Zongman - Chapter 483

Hypnosis, Time Stop, Eyes of Lust...Just why do I have these skills?!After almost dying, he was reborn as the demon king of lust.Since the world is against him, there was no reason for him to be a good person. Especially since the entire world was hunting him down in the first place.So he decided that he would destroy the world in his own way as the demon king.

Grounded in the Transcendent, framed by the Sequence, the Wizard ignited the Source Energy and spewed out a mist of Origin Energy.The roaring sound of steam echoed through the entire epoch!In the depths of shadow and the dark tide.Countless greedy, twisted, polluted, and deformed gazes were coveting this roaring new World.The World began to buzz with activity!A certain Wizard, however, was lurking silently in a corner.“I like to develop!”“Then, what is the deal with those Demon King's heads and Evil God's skeletons?”“I told you, I like to develop, and this is the fate of those who hindered my growth!!”

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

You thought being reincarnated as an extra-side character was bad? Imagine being thrown into the body of a villain who is disowned by his own family and discarded by the author.