http://www.bmezine.com/tattoo/A30419/high/pictures2153.jpg
The character 外 means "out, outside, external; foreign", and the character 宅 means "residence, dwelling, home".
If the tattooed phrase was read from right-to-left, it would mean "the exterior of a house".
But if it was read from left-to-right, then it would mean "outside house" or "out house":
outhouse n : a small outbuilding with a bench having holes through which a user can defecate.
