Terrin is a very private wolf. He rarely speaks of himself, but he is a very good listener, and if he trusts someone, he will give advice is asked. He might even offer it on his own if he really likes someone. He is also very observant. Very little gets past him.
Luna found him on one of her scouting trips. He was injured, and trying to fight off a pack of coyotes. She went to his aid, and the two of them managed to escape. Luna brought him to Lei'luna, and she offered him a home in her pack. Terrin had been a lone wolf for as long as he could remember, but it wasn't something that he enjoyed; for all that he is very private, being completely on his own was too lonely for his tastes. So he was happy to accept.