Internet Mage Professor - Chapter 37: Permission

This is the story of a boy who lived a secluded life in the mountains, tending his farm, rearing his fish, and dreaming his dreams. Eh? Did I suddenly conquer all worlds and become the big boss? Or am I still in a dream?

- Description from Novelupdates

In the ancient land of Yamato, seven powerful clans rule, each upholding their own traditions and strength. But when one clan seeks forbidden power, the balance of the world is shattered. Legends tell of warriors destined to rise, of a hero who will walk the sacred path, and of a battle that will shape the future of Yamato. As alliances are tested and enemies emerge from the shadows, the line between justice and power begins to blur. Will strength alone decide the fate of Yamato, or will a greater force change its destiny forever?

Yuki, a high school junior, dies heroically saving a stranger and is reincarnated in a fantasy world, where he discovers an extraordinary and unrivaled power.

I was a 28-year-old researcher in Japan, and before I knew it, I have been reincarnated in a fantasy world.

Furthermore, I had a half-spirit father and a spirit mother.

An aunt who is deeply attached to father, cousins who are problem children. Girls who cause awkward situations as in an otome.

Furthermore, in order to gain the affection of a love interest, a cousin even had a word battle with a king!

I am very busy helping humans as well as spirits!

And when I find people who are targeting my father,

「I’ll crush you.」

The cheat protagonist deters those who aim at her family. This is such a story.