Mr Bodyguard, Protect Your Heart! - Chapter 18: DO WOMEN NOT HAVE NEEDS OR DO MEN NOT HAVE CHARACTER

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

Lucas was the last human in the universe.A cosmic-scale war had consumed humanity in massive destruction. As collateral damage, there were no longer any habitable planets. Lucas Alhamera, a scientist, attempted to terraform a planet resembling Earth called Antroseda but continuously failed.Overwhelmed by despair and the crushing weight of loneliness, Lucas attempted to end his own life using a euthanasia capsule. However, just before his life could be taken, he was abruptly awakened by a notification.[As the last of the dominant species, you have been chosen as the new Overseer of this universe.][The cycle of life must continue to preserve balance.][Select planet as the birthplace of the new species (default)][Select another planet...]With the Overseer System he had obtained, Lucas began what he had failed to do for hundreds of years: reviving a dead planet and creating a new race to succeed humanity.

After losing his parents to an accident, Haruto is thrust into a state of depression. Realizing he never had the power to change things, he eventually took his own life. Before moving on, he’s selected by beings greater than his understanding to balance out a world suddenly facing peril. The world of Mordell, where demon-like creatures and beasts roam, and Guilds of ability users called Warlords are the force to combat these creatures. Armed with the power to change things, he has the choice. Continue living in despair or accept his second chance and become a true Warlord.

I found myself possessing the body of a young master who everyone was eager to kill. I’m invincible, so let them try to kill me. It’s only for one second, though.