MTL - Quick Transmigration System: Male Lead, Don’t Be Anxious! - Chapter 5 High IQ's strategy overwhelming 3

I, Zatiel, Abyssal Lord, Ruler of Death and Destruction, Nightmare of Dys, have AWOKEN!!!!!.

His life contains events that can shake the universe:
-Fighting against Tiamat, Creator of Evil Dragonkind, in the first circle of hell, while billions of demons and devils butcher each other beneath them
-Start a World War against the Heavenly Race, and transform himself into a Golden Sun while he slaughters their greatest warriors, the Archangel.
-Enter the Final Gate and fight against the Outer Gods.
-Tearing the nine levels of Baator during his battles against the Prince of Evil, Asmodeus.

With his memories as a ruler of the Abyss and a Universal Existence, Zatiel will rise again.

There was once a hero.

Unique black hair. Excellent eyes. Contrary to his delicate features, he who had abnormal strength was called the Otherworldy Hero.

At the hero’s long adventure (up to the point where his wooden sword that had been kindly granted to him by the king was replaced by the holy sword blessed by the holy maiden) he saved the prince that had been kidnapped by the demon king, and so the kingdom was swept by worry.

The hero’s strength that could fell the demon king was deemed too dangerous to leave unrestrained.

One advisor spoke up. Why not marry him to royalty?

The king thought that was a viable option. Family, to an alien from another world would be the best of chains. There was one problem. The king was abundantly blessed with sons and had princes galore, but not a single daughter.

Ho, and it wasn’t like I could marry off two boys.

At a burst of inspiration the king slapped his knee.

That was it!

You just had to turn a prince into a princess!

And so the hero ended up in a position to be marrying a man.

This story, is a tale of the aforementioned otherworldly hero, and his bride, the former-prince-now-princess and their ridiculously hilarious marriage.

This world is Heaven.

Because this world has everything you dream of, everything you wish for.

This world is Hell.

Because everyone in this world are parts of a never-ending massacre.

Are you fighting to survive, or fighting to come home?

- Description from Novelupdates

I exist in the darkness, disappear under the bright light, and will eventually devour the sun and turn into the shadow of all things… Known by people as the indescribable terror of darkness; the king of shadows; the dark day; the existence of the shadow of the world , is still just a somewhat special high school student, facing a weird death game…

- Description from novelbuddy