(Hey, this is my second fanfic and my first attempt at a crossover, this also has some spoilers for Mob Psycho 100, I recommend you either watch or read it, it's really good and was made by the same guy who made One Punch Man. It also has spoilers for Pokémon Super Mystery Dungeon so if you don't want to see that, now is the time to back up. As always, enjoy!)

Disclaimer: I have only watched the anime and have not read the manga(web comic?) so I do not have all information on Mob, only up to after Reigen went 1000%.

"Speech"

'Thought'

Kageyama "Mob" Shigeo is a boy attending Salt Middle School and is the most uninteresting person there. At least, on the outside...

You see, Shigeo is an esper, a very powerful one at that, able to influence his surroundings with his psychic abilities and he wants absolutely nothing to do with it. He strongly believes that he does not require psychic abilities to live a fulfilling life and he was taught those ideals by his master, Arataka Reigen.

Reigen is a con-man and has set up an office where people with problems about spirits and such can go and have their problems fixed. That seems fine but Reigen isn't an esper. That's where Shigeo comes in, exorcising real spirits while Reigen deals with the fake problems(usually with massages).

While Reigen doesn't have psychic powers, he is excellent at conversation and knows how a person's head works, meaning an argument with him would be a lost battle. Since he has this skill, he is able to help Shigeo with any problems he has, especially Shigeo's opinion on his own psychic powers. Even though Reigen is using Shigeo for his business, he genuinely cares about him and looks after his well-being.

Back to Shigeo, he suppresses his immense power because he doesn't want to use them at all but sometimes, if his emotions become erratic, he can't hold it in and his power spills out, an unstoppable force if it is used as an attack. His emotions are measured from 0% to 100% and when he reaches that point, he "explodes".

But enough introductions, we can finally begin this adventure, and it starts with Shigeo walking home from school. He crosses a street and walks down a sidewalk, his eyes never changing and his bowl-cut lightly bouncing in time with his steps. He is in his school uniform and doesn't have work with Reigen today. As he is passing an alleyway, a sound erupts from within and Shigeo stops and looks down the narrow space. A stray cat was scrounging around a dumpster and knocked over the lid.

Shigeo looks at the animal and turns to leave when the cat hisses and jumps away from the shaded area of the alley. Then, it was gone.

Shigeo stared at the feline's previous location and he dropped his bag onto the concrete as he moved towards the spot. He felt a spike of energy when the cat disappeared and he promptly said: "Hello? If you are a spirit, please show yourself and return the cat."

Not but a moment later did a gust of air plow through the alley, sending loose trash into the air. A pink aura rose out of thin air and materialized into a strange monster of a spirit, sharp blades were it's arms and the lower half of it's body were a mess of tentacles. It rested just above the ground, it's large, one eye staring at Shigeo's two and it's smile was riddled with fangs. It suddenly responded in a high pitched voice, giggles in between every word, reminiscent of a psychotic person.

"And who are you to tell me what I should do? I have a special talent, did you know? It allows me to get rid of bugs like you!" the spirit rhymed as it swung a blade at Shigeo, the blade producing a wave of energy, speeding towards him.

He stepped to the left and his bag, which was behind him, disappeared without a trace.

'Is it teleporting them or destroying them?' Shigeo wondered and realized if it was the former, it didn't matter if he had a shield up, he'd just get teleported with his shield.

"Heehee, it won't matter matter where you end up, as long as you're away from me!"

It swung and another wave zipped through the air, which Shigeo dodged again and this time, he lifted his hand and the pink spirit slammed onto the hard ground, cracking it and the walls slightly too.

"WHAT!?" the spirit screamed as it raised it's face from the ground, anger in it's now frowning eye.

"No, no, no, NO! You get away from me RIGHT NOW!" It shouted with such volume as it raised both blades and swung both many times as Shigeo lifted his hand and clenched it. The spirit's body blew up in an array of colors and swirls as gusts of wind lifted trash and Shigeo's hair waved with the force, as if it were dancing. Meanwhile, the attack of the spirit rushed at him with incredible speed.

"NOOOooo..." the spirit cried out before fully disintegrating.

"Huh?" was all Shigeo could say before he was no more.

The alley was now quiet and any evidence of an event occurring was the damage to the ground and walls.

Kageyama Shigeo was declared missing later in the evening.

(This is the end of chapter 1, surprise, surprise. Anyways hope you enjoyed it, chapter 2 will come up sometime soon(hopefully)so I will see you guys later, bye!)