Crossover: The Port Mafia at 100%

Mob, the psychic who's been around for ten thousand years, starts attending Yokohama First High School today.

Why He Enrolled

Reigen Arataka: Mob! Congratulations on graduating! At last, at last, you're about to enter the world of high school!

Kageyama Shigeo: Thanks, Master, but that's a year from now. There aren't any jobs today, are there?

Reigen Arataka: Hey, hey, it's been a whole year and you still haven't mastered the advanced social skill of reading the room?

Kageyama Shigeo: ...You were the one who said, "You're the protagonist of your own life," remember? That was pretty irresponsible...

Reigen Arataka: Then take some advice from your irresponsible master: skip a grade and go to high school in Yokohama!

Kageyama Shigeo: ??? Okay.

Reigen Arataka: Actually, Mrs. Tanizaki asked me to exorcise a spirit for Miss Tanizaki.

Kageyama Shigeo: So, Master, you...

Reigen Arataka: Yeah, I got kicked out without a shred of mercy! Is it because my hair was a little too short? Is it because I hadn't shaved properly? She looked so cute in that uniform, too!

Kageyama Shigeo: So I'm supposed to be the next student in a girl's uniform?

For some reason, Mob Kageyama's enrollment as a "transfer student" was then officially transferred to Yokohama First High School.

After that, he met an adult man who was only 2.3 centimeters taller than him. Then he faced the man's boss without batting an eye.

A certain boss: "Wow, as expected of you, Mob!"

And after that, for reasons unknown, the fourteen-year-old Kageyama Shigeo became the Port Mafia's fifth new executive.

Kageyama Shigeo: "? Sorry, I was just there to exorcise an evil spirit."

P.S. It was originally supposed to follow the British Empire arc, but I've changed it. Please bear with me.