The second skin looks like a common grey homespun robe with a hood. However, when a person is loaded with less than 15 pounds of gear and completly closes the robe, it molds to their body and gives them the appearance that they were actually naked. Normal clothing, armor, equipment and such can be worn over the second skin just like they would normally.
Rumors persist of “special” versions of the second skin. Some claim certain robes can change the wearers appearance, others swear it can grow wings and fly or breath underwater, a few even say they are cursed and consume the wearer and live his life in his place. It is unknown if any or all of these rumors are true, but wise people would do well not to put on a strange robe.
When loaded with no more than 15 pounds of gear, including clothes, food, familiars, pets, and anything that does not have a symbiotic relationship with the wearer, when the robe is closed, including the hood covering the face, the second skin stores all the items similar to a bag of holding and takes on the appearance of the wearer so seamlessly that even extensive physical examination would prove hard to detect the robe. The only access to the gear stored while the robe is worn is through an opening in the belly button that can expand to the size required to reach the item.
Because the robe acts similarly to a bag of holding, it reacts to holding extradimensonal spaces in the same manner, that being catastrophic explosions, and the wearer is considered to being inside for the results of the explosions.
With the exception of the belly button, the wearer’s body seems normal. He can see, taste, hear, smell and touch just as well as normal. His pulse can be felt and he can be wounded just like normal. He can wear armor under the second skin, and then more armor over it, but since the armor under the second skin has been stored, it has no effect. While the second skin is in use, it doesn’t detect any more magical than the wearers skin, and everything stored is hidden from dectection as well. While not in use, it detects much the same way as a bag of holding.
The existance of cursed or other versions of the second skin is up to the GM.