my skin is so pale that I feel that you could see through to all my organs... right now it is mainly veins. sometimes I can see my penis.
in a 2d world, if you view it from a 3d world, then you can see everything, inside and outside of everything. were you able to occupy a 4d world, then looking in on the 3d world would give you the same result - seeing both inside and outside of people and objects. you could reach in and remove a person's liver without breaking the skin.
I'm pretty sure that happened to me 2 days ago.