MTL - Machine Storm - Chapter 469 Furutakeya

The gods visit my shop. I travel across countless worlds with them. But then… “This is my sword, the Heavenly Tyrant Blade.” “This is the Ruyi Jingu Bang.” “This is the lightning spear I once wielded.” Their payments are… peculiar.

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

Accidentally transmigrating into another world, the men here are actually used to carry on the family line? !

a man who takes care of the house and children;

Men wash and cook;

Men are not good? Family law service! The mother-in-law is still trembling to intercede!

These days are really comfortable, and Qiao Yi feels that his life has reached its peak.

She must have saved the galaxy in her previous life.

So here comes the question:

Earn money to support your family? No problem, my wife is too skilled!

Best relative? Don’t be afraid, heads-up can beat five!

She hid in the mountains and went to live her own happy life, right?

But who can tell her, how can there be men in this deep mountain and old forest?

(Every collection and recommendation is my biggest motivation.)

- Description from novelbuddy

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.