A vulva (pussy) that has labia minora (inner lips) and clitoral hood that are hidden by the labia majora (outer lips) when the legs are closed. This is in contrast to an outy.
A penis that goes in and out through the anus. People with innys, such as wheeler, have to sit down when making a pp. Also, innys throw off your balance resulting in lopsided body parts, and strong attractions to men.