Pranks! Pranks for everyone! Who: Everyone who wants in. What: Interaction log for anyone who wants to be a victim of Koryuu's pranks. Where: The main island. When: Now? ICly I guess this would last a couple of days. Rating: Probably not as high as NC-83. Warnings: At most some very light injuries, I would think.
All of Koryuu's traps are set up around the main island, mostly in or close to the park, because he knows that's where Kohaku spends a lot of his time. The traps are as follows, and there are a couple of each around unless otherwise specified:
Primera's rings: Fairy and demon magic is similiar enough that he could sense them and manage to locate one of them. He wasn't able to move it, but he's manually moved a lot of flowers close to it, in the hope of attracting silly angels to it. It works just like in the description. Come on, you know you want to pick those pretty flowers.
Pitfall Team Rocket style: A few deep holes, well camouflaged, enclosed by a magical barrier to block escape attempts. If your magic is stronger than Koryuu's it should be easy enough to get out of the hole (provided that you can fly or are a very skilled climber). If not... enjoy being stuck there until someone comes along to help you. ETA: If you still want your character to make it out of the hole despite the barrier, feel free to assume Koryuu's magic is failing right when they're about to escape. He has a lot of things to be distracted by; it only makes sense.
Bucketful of superglue: He did this once, kind of. With paint. But Kohaku never got to experience it! We can't have that. Therefore, some select trees have been armed with buckets full of, well, glue, that will get dumped on anyone who stands underneath them. Strong, quick-to-dry, difficult-to-get-off glue, you get the idea.
[OOC note:] Please let me know in some way if you'd like Koryuu to be around as your character gets pranked or if you'd like him to stop by at some later point. Otherwise I'll assume you prefer to let your character handle it on their own.