'cos you're only in your skin and nothing else
because u are wearing only your skin<br />
the most natural outfit there is ! your birthday suit :)
Because you look skinnier without clothes?<br />
Or maybe because you're only wearing your skinny.
something to do with it only swimming with your skin.
Because stout people don't do it...
because you dip in the water in just your skin. Or, if you're a little overweight, you can call it chunky dunk