Damn, I Have to Marry the Strongest Antagonist at the Start? - Chapter 526 - 522-Gathering of the Strong

After Reincarnating into Naruto World at the Warring State Era as an Uzumaki, Masahiko thought that he got a useless System. He lived for 48 years as a normal, below average Uzumaki Shinobi.

That changed when he finally knew how the system works the day of his 49th Birthday!

- Description from Novelupdates

In a world where magic rules and human nations fight to survive, a 14-year-old stowaway finds himself thrust onto the frontlines of war. With no allegiance but to his own cold logic, Lugh is forced to navigate battlefields of steel, sorcery, and shadows. What begins as an escape soon becomes something far greater—whether he wills it or not.Gunmage – When spell and steel collide, a new kind of warrior is born.

Marry him for a contract, but it is love that supports them to live together.

In order to raise medical expenses for the seriously ill father, she had to sign a contract with a strange man, she would be his wife, and he was responsible for paying for the treatment of her father.

Life after marriage is very ordinary. He is the CEO of the company. He is busy working every day and occasionally has a look at her, but he is full of disgust. However, she fell in love with him little by little, and she was very sad when facing his indifference. Neither of them knew how to resolve the misunderstanding between them.

After experiencing the death of her father and an unexpected pregnancy, they finally opened their hearts, and sincerely, began a happy life.

«Bleh.» — Imp. An Imp, a monster known to kill with a grin, a demon of the world, a creature of incredible might! Something that no force in the world can stand against! At least that’s what the Main Character would like himself to be, the reality is very different, however.

Exactly that Imp stumbles along a path of unfortunate fortunes and grows through it, in a world that hates its very existence.

It grows more intelligent, more powerful, simply better at whatever it needs to do. Amongst other things, that includes raising children, killing Soldiers, and carving wooden figurines for money.