MTL - After Marrying the Sick and Weak Son, I Turned Around (I Turned Over A New Leaf After Marrying A Sickly Lord) - Chapter 288 really want to kill you

Tenjou Yuuya has been a bullied boy since the past.He lives in the home of his beloved grandfather while he goes to school. As usual, he receives a harsh bullying, and he takes an extended absence from school to have some time to heal his wounds.While on this long time of absence, he takes the opportunity to clean his grandfather’s house and goes to a room he never went before, where his grandfather keep many different objects that he gathered from his travels around the world. While he was arranging the objects, he found a door not on a wall among the objects.Out of curiosity he opens this door, what he found on the other side was…

A mental patient, or a born policeman?

A peerless genius, or a master of crime?

There are cops who are least like cops, and there are criminals who are least like criminals.

Neither good nor evil is absolute.

It is a grey world we live in.

- Description from Novelupdates

When the spiritual barrier that has been intact for a hundred years is shattered by a meteor, spiritual energy that had disappeared starts to return.The mystical realm slowly begins its revival—magic, witchcraft, curses, supernatural lifeforms, strange and mysterious legends, monsters and gods from other worlds…The old world order collapses, yet the new order is mystifying and chaotic.Just before the unprecedented reformation is here, Tang Qi awakens and finds himself hung on the cross, having turned into an inferior demon and in great pain and agony…With his special ability to see through the nature of all things from the mystical realm and a sly and crafty mind, follow Tang Qi as he develops new skills and powers—as well as making new friends and allies—to battle and protect himself from never before seen supernatural threats in an unfamiliar world!

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.