24 Disaster waiting to happen
I haaadd to do this –evil smirk- Mukuro kicks ass, I wish there was more of her around (though it could be that I just miss it as I'm rather Kurama-centric with what i read). I was kind of inspired by one fanfiction that had Koenma send Mukuro and Hiei to Hogwarts to teach DADA, unfortunately I can't remember the story or author's name. My bad!
Mukuro had wanted to see the human world for some time now. She had never been and was curious to see how it had affected Hiei, and why his friend had chosen to stay there. Up until Yusuke's arrival it had just been a place lower class demons sometimes fell into and a source of food for a small part of the population. Now that she had lost the tournament, her queendom, and most of her bloodlust she was bored. Her people were out on Enki's business picking up lost humans or keeping general peace. She made her wishes known to Spirit World, the barrier was down and she intended to pay the human world a visit.
This made Spirit World incredibly anxious. Koenma, after his tantrum, spent days trying to find a way to convince her to change her mind, and after this failed he sought a way to at least channel her energies and attention and keep her occupied. Away from normal humans and under supervision were the two points at the top of his list. He always had Yusuke he could call on in an emergency, but he couldn't have Mukuro sitting around the Yukimura noodle shop with her fellow ex-royal, he needed something diverting.
And that's when he had his brilliant inspiration. The magical community! He would send her to bother them. A decent witch or wizard could take out most minor demons and if they were quick on their feet and with their spells they normally stood a decent chance against the D and C class demons that made up most of the human world demon population. They wouldn't prove at all threatening to her, but they should be powerful enough to entertain her especially the ones who had developed elaborate wand tricks to make their lives easier.
From one of his many overflowing desk drawers he pulled a fresh sheet of paper, the Spirit World letterhead glowing at the top. It was only a matter of moments to write the letter. The old man still owed him anyway, that business with the boy a few years back had been tricky, they had been expecting him to die, the ferry girl had even waited around for his spirit to rise from the wreckage. The way Koenma figured it Hogwarts' headmaster couldn't possibly object to his request that he show the demon around, and even if he did object, well there was no way he could stop her. Koenma sealed the envelop and kissed it before summoning an ogre. "Disaster averted!"