Tennis Buttock

o caboose, originally a ship's galley in wooden cabin on deck; also the "rear end" car of a freight train, considered a cute synonym suitable for any audience
o cakes
o bottom (and the shortening "bot" as well as childish diminutives "bottie" or "botty"), but the use of similar-sounding booty is artistic liberty
o tail (strictly anatomically a zoomorphism, humans only have a tail-bone, yet the illogical tail feather was popularized by musicians; also used for the even more sensual phallus) and tail-end