Leveling Technology To Save Humanity - Chapter 4: The End Is Near

Heartbreak comes with perks?Gao Fei was devastated and nearly fell apart after being dumped for being poor, but he unexpectedly received the Demon God Heritage.From that moment on, he could easily gather wealth, beautiful women, and power all into his fold.What?Now his ex-girlfriend is on her knees, begging him to come back?Sorry, do you think you're worthy?

Orphaned at ten and betrayed by his guardian at nineteen, the protagonist's life spirals into darkness, yet some light remains, only to be cruelly extinguished when his girlfriend sacrifices herself during a brutal demon attack.As a result, he is bestowed with a mysterious system that imbues him with the strength, making him dedicate himself to eradicating demons.Upon defeating the Demon King, he is granted a reward and chooses to reincarnate into a novel-like world with sealed memories until age thirteen.Reborn as the second son of a Duke, he yearns a peaceful life and respite from his tumultuous past. However, fate has different plans.In a world full of political games and supernatural dangers, he finds himself caught in conflicts involving a transmigrator villain and a regressor protagonist.Amid noble family ties, surprising friendships, and veiled threats, he must find his way through this new life, all the while dealing with lingering scars and the chaos that threatens to engulf him and those around him.Can he truly find solace in a world determined to pull him back into the fight?Will he succeed in forging a relaxed and slow life amidst the relentless anomalies at every step?Read to find out!!

Going for a swim, she ends up in an ancient wild Beast World and ends up being brought home by a handsome wolf.
She wants to stick to the handsome wolf, stock some salt, farm some land, look at some handsome men and grow old like that, but the handsome wolf pounces on her every day.
What? He wants her to have babies?
NO~ NO~ NO~ There is no happy ending to interspecies marriages, hurry and let go of me handsome wolf~

- Description from Novelupdates

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.