Start in DxD as Motohama: Leveling Up in Another World - Chapter 13: Unusual Situation (I)

In a world where strength reigns supreme and only the strong are revered, conflict and injuries are commonplace.

As an ordinary human being on the earth, Tang Long was brought to the Cultivation World by a lost immortal, and relying on his amazing talent, he made it to one of the five emperors in that world. However, struck by Thunder of Nine Heavens, he lost his life. It was lucky for him to transmigrate in the human world in an intern who was named Qin Haodong. With his excellent medical skills, he became a divine doctor of traditional Chinese medicine and encountered the baby girl he made before going into the Cultivation World, whose mother was as pretty as a fairy. The little girl even asked him to find more lovers. What a cute girl…

- Description from Novelupdates

“Obtaining the topmost degree of talent in sword arts in the world requires giving up 72 years of lifespan, which leaves you with only five more years of your life. At the same time, you will never be able to feel love, kinship, and friendship, and you’ll end up leading a lonely life until your death, unable to procreate, or to have any descendants.

“From now onwards, everything related to happiness in the human world shall no longer be of your concern. Are you willing to accept this?”

“Hahahaha, I’m already alone bereft of all support, my hopes dashed to pieces, shouldering only absolutely irreconcilable grudge and hatred, why would I disagree? Why would I not want it? I couldn’t ask for anything better!!”

His sword sweeps across the Divine Continent for seven days and nights, moving 90,000 miles through the starry skies, unhindered.

He slays saints and buddhas in Heaven, slaughters demons and devils in Hell, sweeping away all the grievances in his heart!

- Description from Novelupdates

Klaus had spent his entire existence as a puppet, bound by the strings of fate. However, a miraculous turn of events granted him a fresh start. The remnants of his former constraints smoldered in the ashes of his past. Now, unshackled and determined, he resolved to forge his destiny according to his own desires. No one, not even a deity, would be spared if they dared obstruct his path. Klaus was ready to wield the sword of vengeance and carve his own fate in the annals of history.