She Lives without Regret in This Life - Chapter 55 - 0: Second Warning

“I don't want to die anymore, so I'll aim to be the strongest――!”After being stabbed by a random attacker, he was reincarnated in Japan, a place where 'demons' like yokai and monsters exist――and moreover, he was born into a family of 'exorcists' who exorcise these monsters!Exorcism is an important job that involves killing monsters, but it is also a dangerous job where people can die.Therefore, he――Itsuki, made a decision.In order to never die again, he would become strong.He aimed to be the strongest and practiced magic tirelessly since he was a baby――until he realized.“Huh? Isn't this too much?”This is the story of an exorcist who, despite being an ordinary person, became the strongest without realizing it due to excessive effort.

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.

Seo-Joon, who had been working to save money in order to pay off his dead parents’ debt and attend a hunter academy, ended up needing to spend all his savings on a surgery due to an unfortunate accident.In his moment of despair, a weird advertisement played.[You can also become an awakener!]He decided to register since he had nothing else to lose.[Mr. Kim Seo-Joon, welcome to Transcension Academy.]This hunter academy is on a completely different ‘dimension’ than the rest!In the age of private hunter education, you can also become a ‘transcender.’

To save someone, a poor boy unexpectedly acquired Dragon Blood as a body fortifier and even slept with a beautiful female CEO. By a twist of fate, he became the bodyguard of this female CEO, thus beginning a journey of an incredible turnaround.Female CEO, “Come to my room tonight to discuss work.”Long Fei, “Are you trying to kill me? Discussing work every single day for a month, can't you give me a break?”