MTL - Blind Date In Time and Space - Chapter 277 Follow the oath before God and fight for you!

Corporate slave Alexander dies with only one regret—not finishing the fantasy novel in his hands. Fate has a twisted sense of humor when he awakens as Alexander Flamingo, the perverted villain destined to be expelled and killed in that very story!Armed with complete knowledge of the original plot and a mischievous “Harem King System,” Alexander plans to rewrite his fate. No longer the one-dimensional pervert of the novel, he'll use his future knowledge to manipulate heroes, seduce heroines, and rise from disposable villain to the true mastermind of this world.The system grants him power through every relationship he builds—but can this calculating reincarnator use his second chance to avoid his predetermined death and become the ultimate Harem King? One thing's certain: this story won't follow the original script.

# RELAXED # INFINITEDivine-grade Decomposition and Reconstruction System: This allows the user to decompose any object and reconstruct them.…A scraped car? I’ll just disassemble it and make it into a brand new expensive luxury car!A bunch of small diamonds? I’ll just turn them into a 10-carat giant diamond!An old phone? I’ll just make a futuristic phone that won’t appear for another 70 years!”What? Did I get sick? Simple! I’ll just gather a bunch of drugs, decompose them, and make a super medicine out of them!…A few years later, Augmented Reality, the Automated Electronic Management System, air-powered vehicles, humanity's first moon base, and other cutting-edge technologies were all created by a man who was once known as Dumb Lin.

The dawn era after the end of the half century has gradually rebuilt the order, abandoned civilization, and is full of undivided violence and desire.
The noble and powerful pioneers are in charge of the city, and the evil and mad plagues are in the wilderness.
Pure human beings who cannot mutate are the weakest, dominated by the rulers of the pioneers, and are not as good as animals in the wilderness.
A purely humanized young man with a worldly experience has quietly entered the WTO, holding a three-foot long knife and a long-distance desire to boil in the world of purgatory. From the nameless name to the sorrow of the Supreme Court, the name of the black ride is resounding!

- Description from Uukanshu (translated)

This is a cliché story about two young people saving the world.