The Cursed Prince's Strange Bride - Chapter 440 "It’s Always You"

Before going to college, an ordinary high school student went to celebrate and got drunk. When he woke up, he found himself in a completely different world. There was a big sect, the approaching sect entrance examination, a slum where his body’s previous owner lived, and a shared memory about a missing young girl.

When he got tangled in a fight with a few punks in this different world, he fell off a cliff and miraculously found himself still alive, with two more voices ringing inside his head. They were Sword Master and Saber Master. In the company of them, he continued to find out more about this whole new world. He took the sect entrance examination, entered the sect, met a strange man in black, and even participated in a major competition of the sect to have a chance to win over his peers!
In this whole new world, he was born again and got to explore the fantastic martial world!

- Description from Novelupdates

Xiao Ran transmigrated to a fantasy world. As a dungeon guard in the Celestial Dungeon, with a special floor called the Purgatory meant for powerful demons and martial arts experts, he faced a huge challenge from the start. The Eldest Princess acquired a forbidden martial arts technique and was banished to the Purgatory. However, no one was powerful enough to restrain her. All the dungeon guards were defeated. Xiao Ran stepped up and declared, “Your Highness, it’s better for you to behave yourself on my territory” and effortlessly subdued the Eldest Princess.

He progressed from imprisoning the Eldest Princess to delivering the Great Xia Kingdom from the evil clutches of various demons and evil martial arts experts.

…

Xiao Ran was the mastermind behind the scenes.

You shall become king—

Ruling over all “serpents” in the world…

Become the man who bears the brunt of dragonkind’s fear and hatred.

A modern era when humanity is threatened by attacks from giant dragons flying from beyond the sky.

Controlling “leviathans”—serpentine spiritual beings created through magic—humanity is locked in a protracted war of resistance against the dragons.

Fortunately, there exist witches known as “magi”—battle maidens of salvation who formed covenants with “serpents” in order to combat dragons.

Nicknamed Hal, the young man called Haruga Haruomi makes his living through facilitating the covenants of these girls.

At the (partially coercive) request of his childhood friend Asya, one of Europe’s top witches, Hal returns to Tokyo New Town after an absence of three years.

Accompanied by the beautiful Asya whose appearance rivaled a fairy’s, Hal is running all over the place to secure his base of operations and taking care of matters related to school transfer when the elite dragon Soth suddenly attacks—!?

Life has been breathed into a brand new myth between dragons and dragonslayers.

A grand opening to the “birth” of a top-class battle epic!