Werewolf is a man who can transform himself into a wolf at night (shapeshifting ability).From the Slavic and Germanic mythologies.What about using this pattern?
There was a mod (search: Curse of Hircine), which adds just this feature into the game. Unfortunately it was really buggy and had all sorts of in-game issues, and now development of it has ceased. However you can download, the alpha, it's useable but requires OBSE.
M.O.E had a nice version of Lycantrophy
I saw that at Midas spells mod.
m.o.e dosen't need obse so m.o.e's is better.
An alternative to using OBSE could be to make use of equipable armour instead, but that brings its own problems from what I hear.