Sphinkty
A "sphinky (" ss-ff-ink-tee")," is a term or slang for sphincter, which is inside of the anal cavity. People most commonly know this area as the butthole and or anus. In some places it can also be called the anus but is mainly used in the slang term sphinkty in a joking manner.
She had that cucumber so far up there it touched her sphinkty!