MTL - Demon King’s Political Marriage - Chapter 3 Pre-marital training (medium)

Earth is dying. The sun is expanding at an uncontrollable rate, but Theo Spencer is alright with this. He's led a deplorable life. When the end comes, a mysterious entity grants him the gift of reincarnation. The gift of a quiet life as an alchemist.

Theo awakens in a small town in the southern reaches of a small kingdom in a non-human body. Broken Tusk doesn't seem like much, but his legendary alchemy skills will soon turn their fortune.

Join Theo on his journey to turn the swamp-town of Broken Tusk into a prosperous trade town.

As a virtuous wife, does it include tolerating his cousin, enduring his concubines, bearing his mother?

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.