I can rewind time to prevent death - Chapter 685 - 413 Huh Aunt Mei_2

First World : CampioneCurrent - Second World: High School DxDThird World: ???Reincarnated into the world of Campione! Haru Kasugano, our hero slays gods and ascends as the mightiest Godslayer. He battles powerful God-Kings and Campiones, claiming victory after victory. Whatever it is. [Wealth, Power, Beauty] he has it All. Watch him grow stronger as he travels into new realms like High School DxD and the Fateverse, leaving a trail of defeated gods and captivated hearts in his wake.

Yggdrasil, the World Tree of Norse Mythology, suddenly appeared on Earth. And with it came demonic creatures that ravaged entire cities.Although not all hope is lost, due to the System that a few special humans had gained.In this new world where only the strong survived, Min JaeHyun scrapes by regretting the wrong choices he’d made in the past… when one day, he gains the only Mythic item in the world.How will this item help him? And can he change his wretched fate?

In the era of universal mechas, people can go to the endless abyss, collect materials, strengthen and forge their own mechas, and master the power of destroying the world.

Jiang Chen traveled through time and awakened his talent [Immortal Unarmed]. Once the mecha is broken, he can permanently absorb its power and receive multiple bonuses.

…

At the bottom of the abyss, when the Old Demon God finally broke the Titan mecha with great effort, a hand stretched out from the fragments and held down its head.

“Congratulations, you have unlocked my limiter.”

- Description from novelbuddy

This book is about Jay (ceo of Mariano Enterprises) and Keifer (ceo of Watson Enterprises) falling in love. Ofc Jayfer is the endgame :)