I Leveled up from Being a Parasite, But I May Have Grown Too Much - Chapter 111: Elder Necromancer Demirich Part 3

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.

Transmigrated into the body of a cannon fodder villain, Chu Yu has three major worries:

1. How can he help the protagonist turn into a real harem master?

2. How can he develop a good relationship with the protagonist?

3. How can he live properly without holding on to the protagonist’s thigh?

The protagonist has three major worries:

1. Eldest disciple brother has changed

2. Eldest disciple brother has really changed

3. How can he marry eldest disciple brother?

System: Congratulations! ~ Sprinkle Flowers ~ Grow Old Together Happily!

Chu Yu: … Wait, what about the harem novel?

Author’s Note – This 1vs1 (no harem) And HE (Happy Ending)

- Description from Novelupdates

An 18-year-old poor college student tried to apply for a job as a tutor but his life almost ended as demons' meal. In his last breath, a mysterious woman gave him a strange power. When he opened his eyes he had turned into a demon with a system that would turn him into… A pervert.

Now he must lived with his dual identity as a model student named Ethan and an incubus named Damian.

The more he got to the Comprehensive world, Beiyuan Baiqiu originally thought it was just an ordinary Comprehensive daily world.

Who would have thought that after entering high school, unusual things would happen one after another, and I would awaken myself through the simulator.

Since then, Beiyuan Baiqiu has embarked on the road of being invincible.

[Demon Slayer, Campione!, No Game No Life, Problem Children are Coming from Another World…]

- Description from novelbuddy