Lifting up a person's skirt, usually with the intent to show off their underwear or bare crotch/butt. Usually this is done either by the wearer of the skirt or someone nearby. It could also be caused by an inanimate object, such as a hook or other object that might catch the skirt and lift it up. It can be done voluntarily or involuntarily (by another person/object).

This tag can be used for the lifting of the lower part of a dress. Example: post #60029

(Partially copied from Danbooru)