Starting With Contract Pets - Chapter 238 - Noiselessly

The little handsome son-in-law passed through a world as waste material and the husband of a wealthy family. But because of his lacking aptitude, the wealthy family had driven him out. So he worked hard and found a more powerful family’s thighs to hold onto. Soon enough, he became the strongest son-in-law and husband in history.

In this world, it was impossible to practice martial arts. It was futile so he might as well take advantage of his wife’s thighs and maintain a comfortable and leisure lifestyle.

He’ll train his wife to become the strongest and best person in the world.

“Whoever dares to provoke me, let my wife kill you!”

- Description from Novelupdates

A young man, a modern-day history and war enthusiast, finds himself reincarnated in the body of an orphan — one destined to inherit a small, struggling barony from his dying uncle. But fate offers no easy path. Inside the family, greedy rivals lurk, eager to steal his inheritance. Outside, hostile neighbors eye his weakened lands, ready to tear it apart at the first sign of weakness.This is a tale of ruthless ambition, cunning strategy, and relentless struggle. From a powerless orphan to a baron, from the weakest barony to the mightiest duchy — he will rise through blood, steel, and fire.

Before Li Daniu had time to be excited about being a prince who was about to ascend the throne, he learned that his country was about to be submerged by sea water.

“Can I wear it back?”

- Description from novelbuddy

16 years old-- most boys would be falling in love, as their hormones all rise to unprecedented levels. Most boys at Riley's age would have dreams; dreams that will slowly grow into passion. Riley, however, at age 16... killed the world's number 1 superhero.