Info/Permission
Name: Hidan
Age: Unknown
Hair: Silver
Eyes: Violet/Magenta
Height: Unknown, but judging from the most recent volume cover...between 6'0" and 6'2"?
Weight: Unknown
Bloodtype: Unknown
Medical info: Very strong, healthy, heals unnaturally quickly, is immortal (i.e. still talks after he's had his head cut off)
Physical Traits: Pale-haired and pale-faced, tall, almost always has his scythe on him...this in a nutshell. His special ability involves him taking on a skeletal appearance (like in the post icon) after consuming a small amount of an opponent's blood, at which point whatever damage he inflicts to himself manifests in the opponent until he/she is dead.
What's Okay to Mention: ...I would say it's easier to just see what's not okay to mention and make your judgments from there.
(What's Not Okay to Mention:) Religion-bashing. Celibacy-bashing. Whining and complaining in general. His mom.
Notes For the Psychics: It's really messy up there. XD Is not ashamed of anything, either, so prodding around is fine.
Hugging/Kissing/Nicknaming: Nicknaming he can handle to a degree. Hugging is very rarely tolerated, and even then you'll probably get hit. Kissing is an invitation to be decapitated.
Maiming/Killing/Death: Maiming and attempts at killing are fine. Actually killing him is impossible. Making an attempt at killing him will earn you very violent (and probably very messy) retaliation.
Other facts: Hidan is a connoisseur of vile language. :D