A Hentai System in the World of Danmachi - Chapter 27 - 26 - Fucking your best friend. +18

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.

Every trace of my entire youth is engraved with the same name.

When I see the trees on the street and the clouds on the horizon, I will think of him unconsciously.

I remember the bubble tea he ordered for me, and the sparklers he lit up for me.

Those memories supported me through difficult days and made me think I was special at one point.

When I was young, I often wondered, is it possible? Even if it is one in ten thousand, what if I am the heroine in his story?

I have said goodbye to him countless times, on the phone, on WeChat, face to face, every time without pressure, because I know there will be another meeting.

But this time is different, Xu Jiamu, this time I really want to say goodbye to you.

“Goodbye, Xu Jiamu.”

- Description from Novelupdates

Darkness’ devouring energy and mysterious space energy.

The two different types of energy appeared in one person.

A glance that can kill? That is the power of space.

Men will be r*ped by beautiful women?

That is the fate of the protagonist?

In a world with Special powers, Vampires, Witches and Demons,

where the forces of Darkness and Light collides.

His women will be his guiding lights and change his fate!

– from eveningBoat

- Description from Novelupdates

In the previous life, Jiang Peihuan was tricked by a scumbag and died tragically, which even caused her entire family to be wiped out.

When she was eighteen years old again, she was still the arrogant girl who refused to give in to her husband.

Her fiancé thought she had fallen into the water and lost her virginity, so he came to break the engagement and marry her cousin?

Everyone laughed at her, but she was happy to see the result: one hundred thousand taels of gold, I agreed to it.

After retiring from the engagement, it was rumored in the capital that she was abandoned when she was about to get married.

Unexpectedly, that unparalleled His Royal Highness Cheng Wang stood up: marrying her, why not?

Many well-known ladies’ spring boudoir dreams were shattered, but Jiang Peihuan was very moved and refused.

He is the emperor’s uncle of a scumbag, the youngest son of the late emperor, he looks suave and noble, but in fact he is ruthless.

She vowed to avenge her past life, protect her family and relatives, and did not want to have anything to do with the royal family.

But finally one day, she still accidentally became the envied Princess Cheng.

Jiang Peihuan recalled it, and became angry at the man lying beside him: Xiao Nanye, are you plotting against me?

His Royal Highness Cheng Wang, who was decisive in killing, couldn’t help laughing when he saw his concubine blowing her hair.

He whispered deceitfully, with a lingering voice: Forgive me, forgive me, I only want you alone in my life.

- Description from novelbuddy