MTL - The Life After Marrying My Sworn Enemy - ~ Section 16

Xiao Yu, who was a student from modern Earth, accidentally transports to another world and becomes the lord of a territory. Facing an unfavorable situation, he vows to take back his family business, build his new territory, kill all of those who covet his wealth, and dominate the world!

In the waves of steam and machinery, who could achieve extraordinary? In the fogs of history and darkness, who was whispering? I woke up from the realm of mysteries and opened my eyes to the world.

Firearms, cannons, battleships, airships, and difference machines. Potions, divination, curses, hanged-man, and sealed artifacts… The lights shone brightly, yet the secrets of the world were never far away. This was a legend of the “Fool”.

- Description from novelupdates

When a cold and crafty girl travels into the body of a foolish, man-crazy, young female aristocrat, what will happen?

Once upon a time, the Devil fell in love with one of the King’s many wives. One night he went to her room disguised as her husband and made love to her. She got pregnant with his child. Knowing this The King ordered her execution believing his wife cheated on him, but then the Devil appeared to the king making him a deal. In exchange for great power for his Kingdom, the King will let his wife Sire The Devil’s Child. The King who was greedy for power agrees to the deal and his Kingdom becomes one of the most powerful Kingdoms and the Devil’s Child, the seventh Prince of the Kingdom.