From Apocalypse To Entertainment Circle (BL) - Chapter 8: Blood in the Spotlight: Prelude to a Massacre

Kamishiro Homura is a hero who once by himself exterminated the another world invader that destroyed the military all over the world. However his extreme strength made the influential people ostracized and exiled him from the society with false accusation of [Traitor] attached to him. A few years after that, for an unspecified reason Homura entered the magician academy and he looked after the girls that were ridiculed as the [burden platoon]…!? This is the raise of the curtain of a fantasy tale of the unrivaled and invincible young man where not a single ally or enemy can keep up with him, the young man who sooner or later will be extolled as the messiah by the whole human race!

Lynn traveled to a magical world similar to the European Middle Ages but possessing magical powers.

Here, magic can affect and control elementary particles.

So…a scientific theory is a magic formula!

Wizards called spellcasters who are actually scientists, under the siege of the Holy See, struggled to explore the truth of the world, until the arrival of Lin En, which set off a renaissance of an alien version…

(PS: The 2 million-word work “Hogwarts Bloodline Wizards” has already been completed, and the quality is guaranteed!)

- Description from novelbuddy

The protagonist of a war fantasy novel, Theo, competes with his rival and antagonist, Luke, for the position of Supreme Commander. Having been reincarnated into Luke’s role, he struggles to fulfill his duties as the villain. “It seems like principles as a soldier, the duties I should uphold, don’t matter to you at all.” Even if misunderstood by Theo, Luke silently remained faithful to his role as the antagonist. After completing all his duties, Luke successfully gave Theo his happy ending, cast aside his military uniform, and retired from the army. Now, Luke planned to create his own future story without interference from anyone. That was the plan, at least… “Why go this far? I’m no longer a soldier, and if you really think about it, we were never on good terms anyway.” To make matters worse, not only had he unexpectedly reunited with Theo, but now, Theo was persistently and seriously pressing him in a way he hadn’t imagined. “I want to know you better.” It was a completely incomprehensible statement, and it wasn’t even an appropriate answer to the question. The protagonist came to the antagonist and suddenly asked for help, simply because they wanted to know him better?

Beings that create and control monsters and demons, beings that build and reign over malicious labyrinths, the chosen individuals to possess an overwhelming Unique Skill… They are the Demon Lords.