Wolf hair?

I can hear your thoughts Monk. Oh yes I can. You're thinking, "It's all become a bit one track again." Well you're entitled to your opinion. In an attempt to avoid such things:

Where do the hairs of werewolves come from?

We all know the theory. A werewolf bites you, you get infected and you become one. Every full moon you transform into one of the large hairy beasts, but these hairs seem to grow from inside your body. Are these hairs there all the time? Are they spontaneously created as part of the change? Is it magic or accelerated genetic resequencing? The latter would explain the ability to grow a snout and whatnot too. Then again so would magic, so we're not much further ahead.

And whats with the memory loss? Why force someone to commit horrific acts, then not let them remeber them? True it's funny to watch someone wake up in a room full of blood to find out none of it's theres, but that could get old.