Skin Window

The act showing someone your penis skin through the fly hole in your pants or underwear.

Todd and Ted are chillin with some brewskis when Todd calls over to Ted, "hey bruddah, peep dis", Todd had pulled his shirt up and made sure his pants were unzipped making his penis skin visible through his pants forming the skin window.

Skin window

The part of a dolls legs between her sexy high boots and fancy dress

You see that skin window on that pocket ninja.