MTL - Paradise of Demonic Gods - ~ 1269 Timeline changes

A modern-day antihero, who was infamous for his devious acts, dies in an explosion meant to take down a powerful criminal syndicate. Waking up in a world of sword and sorcery, he finds himself possessing a fragile, powerless body with a strange “System” that seems broken. Initially thinking he's doomed, he learns that by pretending to be weak, he can manipulate others into revealing their secrets, granting him abilities they possess. As he rises in power, he discovers that the System was intentionally sabotaged—by none other than his own future self.

Once, because of a pair of purple eyes he was scorned. He is a wangye known across the land, cold and bloodthirsty, looking disdainfully upon the world.

Once, because of a mother’s death she received a father’s resentment. She is a publicly known junzhu whose looks have been destroyed, pitiful and weak.

In reality, he has a pair of this world’s most beautiful eyes, the most formidable background, the most imposing strength.

In reality, she has a peerless face, the most unshakable background, and the most ingenious medical skills.

She, Lan You Nian, aloof and cold-hearted, underneath the appearance of a celestial maiden is a battered, wounded heart.

When the cruel and ruthless him met the indifferent her, who adores who most deeply? Who once again puts a smiles on for whom?

- Description from novelupdates

A polite and lethargic boy was reincarnated in another world as a vampire bishoujo.

This is a story about the protagonist getting the system, going crazy in the biochemical apocalypse, producing aircraft and tanks, destroying zombies, saving good people and killing bad people.

- Description from novelbuddy