the world's on fire and I just want an excuse to give him wolf ears and a tail off and on. pet the dog.

Which is to say, it's a blessing that just manifested on the ship, he cannot control it and it probably happens when he loses control (using that loosely) and goes away when he's calmed down for a period of time. The more he freaks out, the more wolf he becomes but it generally stays to just like, ears and tail. maybe claws. control your emotions better, fool.