Kami-sama no Memochou - Volume 3, Chapter 6

Life is unpredictable. Her husband loved her stepsister, deposed her as Empress and even forced her son to death. In that Cold Palace, she was forced to drink poisonous wine. So in the next lifetime, she made a promise to never do good deeds and help others, to never step into the palace and to never become the Empress!

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.

He slides his hand between her legs and pulls her in. She gasps and holds on to him for support as he runs his fingers between her lips and clit. She's trembling from his touch. As he moves his finger around the outside of her.“Time to rinse off” he whispers to her.He uses his body to push her towards the water and he rubs her again he presses the front half of her body to his and washes the soap off her backside. She throws her head back. And begins to let out a scream, but he covers her mouth with his hands and says “shhhhh be quiet now.”He spins her around so her back side is pressed against his erected cock. Feeling it's cold contact she throws her head back again gasping. Her then washes the front of her off pressing hard against her he gropes her breast squeezing them tight and pinching her nipples.She was so surprised by how good this felt.How badly she wanted him to bite her.And just as she finished that thought he stuck his hands between her legs again, and then he bit her on the opposite side of Oliver's bite. The bite burned her core undoing her as he played with her clit with his fingers and then sliding them inside her. Holding her body hostage with his fangs and fingers she completely submitted to his whims. He could have what ever he wanted in that moment and she wouldn't complain a bit.Pulling his fingers out of her and sucking her juices off them he says “You really are the best thing I've ever tasted. And now I know why my brothers are struggling not to fuck you and are fighting over you. I don’t think we can wait until the full moon to start breaking you in.”

Wei Yuewu is the unloved daughter of the powerful Marquis Hua Yang.

On her way back to the capital city to marry her fiancé, she becomes the target of a ruthless assassination led by her fiancé, Marquis Jing Yuan.

With the help of the Prince of Yan State, she narrowly escapes from one disaster after another and returns to the capital.

Determined to avenge her enemies and unravel the mystery surrounding her engagement with Marquis Jing Yuan as well as the death of her mother, Wei Yuewu makes a deal with the Prince of Yan State.

However, just as she has triumphed over all her enemies and is about to reach the acme of her life, she deliberately destroys her own future and becomes an exile of her own…