If the skin is falling off with quills attached, it's probably mites (checking for moving flakes on dark fabric is a good test, but not always accurate). You'll want to take him to the vet to get checked out. Make sure to request that he's treated with Revolution (three treatments, two weeks apart) instead of Ivermectin, as Ivermectin can be lethal.
Hedgie Mommy to little Piglet
* Abby *