Stranger's Handbook - Chapter 130: Bea’s Feelings

The youngest Wiseman of the continent, Chu Tian, has traveled 30,000 years back in time to the age of antiquity due to an accident.

In a parallel world where everyone was a Beastmaster, people would tame, train, and evolve their beasts. The Federal Government would give everyone their own beast egg at their coming-of-age ceremony. However, to evolve and grow the beast, they would need potions, gems, and other rare ingredients. Fortunately for Su Bai, he had awakened the Divine-grade Simplification System. With the system, growing a beast was as easy as it could get. “Lightning Rat detected. The evolution path has been simplified. Plugged in. Evolution points +1, +1, +1…”

“Bubble Turtle detected. The evolution path has been simplified. Shower. Evolution points +1, +1, +1…” “Flame Cat detected. The evolution path has been simplified. Sunbath. Evolution points +1, +1, +1…” A few years later, Su Bai, the Divine Beastmaster accepted an interview. “Mr. Su, can you tell us how you achieved your success?” “I spend my time growing my beasts when other people are showering or sunbathing.”

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 world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.