Quickly Wear the Face of the Devil - Chapter 78

Step into a world where science meets the unknown, where mechas clash in brutal duels, and where every Biocore holds a mystery waiting to be unraveled.Follow Nioh, a genius weapons designer, as he uncovers lost technology, battles biomechanical titans, and pushes the limits of power, in an intergalactic thrilling adventure

Talented in Magecraft but useless in physical combat?

Can summon 10,000 Servants but can he defend the rear by himself?

I will say just one line in reply:

“That will not be a problem!”

This is the tale of a young man who obtained an enshrined miracle.

“As long as I have my familiars, I am undefeatable!”

- Description from Novelupdates

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.

Lived for the sword, died for the sword.