Demon King of the Royal Class - Chapter 498

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

Life can be very unfair most of the time, and Christopher is someone who knows this very well.Being an orphan, his chances of achieving great things in life were close to nil. But things change when he meets his lover. However, a series of events lead to his death.But that isn't the end. He wakes up in the body of someone just like him in another world, and with a system, one with an incredible ability.With his newfound cheat, he completely sweeps his way through the world and beyond.Angels? Demons? Dragons? Gods? Their titles don't matter, because in the end they will only have two options. Submit or die.

In her last life, she was miserable and ordinary. This time, she got into the fashion and was reborn in another world. She was still the same person… even with the same body and face. What was the point of reincarnation? A childhood companion? He always pulled her hair and made troubles for her? A handsome boy? The boy never looked at her and was 15 years older than her! A prestigious teacher? The teacher spent his days eating and drinking, coaxed, played tricks, and controlled others… Too scary and better run away? No no no, such a challenging life was bound to be wonderful! Now let me take you back to the 70s and live a fast life!

- Description from Novelupdates

If you had a chance to live again, what would you do? Earn money, hold onto a thick leg, just find someone to live a happy life with? Ha ha… Stepping on the beat of the times, riding the wind and breaking the waves, strategizing, using your knowledge to change yourself, and everything around you, come back! The reality flows to the plot, the golden fingers are thick, slow, and cool.

- Description from Novelupdates