(Not 100% happy with this ref so please excuse the shittyness)
Bear is a native veteran living at the Xavier Institute in around the 90s era. He teaches a few things to the young ones there, which he enjoys greatly, instead of the alternative of living out the rest of his life on measly vet benefits doing nothing. Mega pipe smoker, and happy enough to drink, he has no qualms about his 'bad habits'. He is stern and often fussy, but also patient and gentle with the younger kids. His mutation transfers wounds from someone he touches onto his own body- and is the reason he lost his limb many years ago.
Read more here- http://w11.zetaboards.com/Bayville/topic/10132217/1/