This Beast-Tamer is a Little Strange - Chapter 618: The Prisoner’s Dilemma

Suzumiya Kaede, a gamer, fell asleep while playing a game all night and when he woke up he found himself in another world, a fantasy world where using magic is possible! Using his knowledge of games, skills, and cheats, Kaede decides to enjoy as much of his new life in a different world through his newly-acquired magic and sword!

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

When I was reborn in South Korea, I wanted to live my life in peace. Pass the activation system, unlock the 'Big Brother' career, obtain the invincible system, and embark on the road to power

Here hundreds of countries compete for supremacy, here hundreds of schools of thought flourish, he brings the strongest family head system, establishes the most powerful family, and steps onto the highest stage step by step!