Mob Psycho 100 X Hito Kui

Mob Psycho 100 X Hito Kui is a crossover chapter of the Mob Psycho 100 manga series with the Hito Kui manga series. It was illustrated by ONE.

Synopsis
With reports of a mass deaths occurring, the "Devourer theory" was one of the most popular hypotheses as to the cause. In Mob's class, they get a new transfer student named "XXXX". Meanwhile, a customer explains to Reigen everything to know about the mysterious "Devourer" that was responsible for all the killings.

That night, Reigen awakes to find himself in a mysterious place. Remembering what he had been told about the "Devourer", he eventually discerns its hidden identity and defeats it, freeing himself and others from the dream world. Meanwhile, a frightened Mob is also trapped in a mysterious place, having been chased by a monster and being unable to use his psychic power. Encountering the monster, he freaks out and goes ???% before destroying the monster and causing Mob to wake up in a cold sweat.

Later, XXXX leaves the class telling Mob he was no ordinary person and the reports of mass deaths stop. When Reigen asks Mob if he had ever heard of the "Devourer", Mob replies that he hadn't.