Name: Jin
Age: Well it never really says in canon, but judging from his height, personality, and mannerisms, I'd put him a couple years ahead of Yusuke...he looks about 17, but it's possible that he's older (since he's a demon, for all anyone knows he could be in the hundreds or thousands -w-; )
Height: About 6'4", since he towers over the main cast of the show. TALL DEMON GET.
Weight: I'd say probably around 200, maybe a little under since he's so skinny. Again, no official canon weight, but estimates can be made. |:<
Medical Info: Jin's fit as a fiddle, as far as demons are concerned. /o/;
Eyes: Deep blue LIKE THE SKY OMFG
Hair: As you can see above, it's BRIGHT red and very, very messy (what are haircuts \O_o/). Kind of like a blood-mop, really. Plus there's that horn sticking out of the top.
Physical traits: TALL DEMON IS TALL! Also, it's probably worth mentioning that he, like, never wears shoes.
What's Okay To Mention Around Him/Her: WHATEVA. Jin's not realy easy to offend or anything, so he's fairly easy to converse with.
Abilities: Well right off the bat, this demon can FLY. And not just in short spurts, he can fly for a damn long time; hell, he tends to lean back and rest in midair. As far as altitude, as long as there's air he can manipulate, he's golden.
Besides that, he's got a pretty strong body. Nowhere near as tough as his BFF Yusuke, but enough that he can take hits pretty well. Still, he's more likely to zip out of the way of punches than he is to stand and take them.
As far as combat abilities, his signature move is called the Tornado Punch. Basically, he whips his arm in a circle fast enough to create a miniature tornado around it, then, you know, punches you with it. The thing is, the winds in that tornado are so effing strong that even if you block it, the knockback force is tremendous; you're going to fly in some direction like it or not. He can have one going on each fist for a double-tornado threat.
Additionally, he can whip up tornados around himself both for offense and defense; the winds can reach such speeds that they can deflect projectile attacks, including energy and spiritual attacks. Plus, you know, if you're standing in a tornado you're gonna be launched skywards, and midair is Jin's power zone.
Can I shapeshift/bodyswap/spit at/step on/etc?: You're going to be dealing with a pissed off Jin afterwards (which is hard to do really), but as long as you get my permission before doing so I have no trouble with it.
Maim/Murder/Death: You're welcome to give it a go, but odds are if you really seem that tough he's going to send you flying cross-island, so don't expect to waltz in and take him down easy.
Cooking: Never really explained in canon, so lolwut.