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1.
a sphincter kiss is when two people. man to man. female to female or male to female, spread there butt cheeks, touch sphincters and pucker thems up to kiss. surprisingly this is very arowsing to some humans but is more common to the primates, orangutans are the primates to most likely to do so.
assholes puckering up and touching to release air into eachother = sphincter kiss
by jack nelson May 21, 2009