Legacy of the Dark Sage - Chapter 65 Regis Special Force

In a world dotted with World Entrances to a demon world, demons have invaded humans for centuries. Humanity has united and one of the most ancient sects in the world, the Archean Mountain Sect, has set up an entire education system in the form of Dao Academies and defenses at the World Entrances.

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

A high school student that has lived as a mob-character ―― Mimori Touka

Houjou Yuuji, 30 years old, jobless, hikkomori for 10 years. Using his parents’ death as the impetus, he decides to rid himself of his hikkomori life and leaves the house. What awaited him, however, was a different world that he was not used to, creatures strutting about that he didn’t recognize.

This is the story of a man transported to the another world, as he lives in relative peace with his beloved dog Kotarou – his house, with electricity, water, gas, and the internet somehow still connected.

One day while exploring the forest near his house he finds a girl named Alice, and becomes her guardian. Thus, 4 years after he is transported to this world, Yuuji resolves to venture into his first town.