Maou-sama no Machizukuri! ~Saikyou no Danjon wa Kindai Toshi~ - Volume 9 Chapter 18

This is the tale of Arin, a once kind-hearted and gentle child, now a man hardened by the cruelty of society and the brutal trials of life—a man transformed into a ruthless criminal, devoid of mercy. As his world was collapsing, fate transported him to a new realm. This world, more vicious and savage than his own, was steeped in magic and dark mysteries.Ironically, it was in this fearsome world that Arin, now an undead being, began to rediscover his lost humanity. Through battles and bloodshed, amidst the clash of sorcery and steel, he started to reclaim the compassion he once hated. This is not just a story of survival but a saga of transformation. Follow Arin’s journey as he rises to power, determined to become the ruler of this harsh world. In a twist of fate, he now seeks to save the very humanity he once wanted to destroy.

Gawain is dead and was transmigrated, but there was a slight problem during the process.
After floating for more than a hundred thousand years on a different continent, he felt that he might need a body to become a complete transmigrator, but he did not expect that…

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

After dying on Earth, Liam Porter awakens in Twin Land, a strange world ruled by powerful Spirit Masters.Surrounded by corpses and the wreckage of a destroyed carriage, Liam finds himself wounded—newly arrived in this new world—facing the man responsible for his predecessor’s death.Thrown on an island where he must survive, Liam survives a strange demonic ritual and awakens magical powers.In a world where magic reigns and mystical beings (beasts and monsters) are essential for the growth of the Spirit Masters, Liam will follow a unique path alongside an incubus demon-spirit!To get stronger, he’ll have to conquer women and tame beasts!But not only his captors and the beasts—Spirit Masters’ natural enemies—will stand in his way. He will also have to face the depraved reality in which he finds himself!…“I will become the new Beasts God! Nothing and no one will stop me from achieving my ambition!”Expectations:- Fast pace, particularly at the beginning. A balance between lots of action, kingdom building, slow analysis of the cultivation system and rune creation;- Dark truths of a medieval society;- The MC is a curious earthling with above-average intelligence. He’s not a genius, but he will bring some things from his past life into this world in order to have some advantages (later in the story);- Harem;- Dual cultivation; (it’s the MC’s main cultivation method);- From weak to strong;- Sect building (later in the story).