human accordion

A sexual position which requires 3 parties. The middle party (female) is receiving a "frown face" on all fours from person in front while person in back is engaging in rigorous vaginal or anal intercourse in a "doggy style" position. The women in the middle is compressed then released in an a motion similar to that of a musical accordion.

Yo, last night me and my boy tag teamed that chick! We turned her into a human accordion!