How is Sajin Komamura a wolf? Sajin Komamura is described as being an anthropomorphic wolf in the Wikipedia article, but everyone in the Soul Society is either someone who died or the descendant of someone who died.  There are (as far as I know) no anthropomorphic wolves in the living world, so where did he come from? Was he born that way, created, or is there some other explanation?
Bleach episode 539 has some answers.

Komamura is talking to his great grandfather:




   Who is a huge canine himself. From this it is clear that a canine appearance is a family trait. The conversation also reveals that they do have a special status, though it is not clear what exactly their role in Soul Society is. It is, however, clear that Komamura was born this way.




Bleach 556 has some further information - in a flashback to his previous encounter with his great grandfather, who says:


   





    So, he is not a wolf, but a werewolf. The clan originated in soul society, were banished, but did come back.