A verb that is used frequently in romance novels describing how a woman's nipple pops outwardly during a scene with a lot of sexual tension or just plain, old-fashioned sex.
Under the gentle but calloused hands of the stable boy, Thomasio, the CountessFiora's desire grew obvious as her breasts swelled and her nipples pebbled.
when the areolae on breasts begin to become aroused, they often get goose bumps which makes them look like they are covered in pebbles as they start to harden and tighten.
When watching Supernatural, Lilly could always gauge how excited Dean made her by lifting her shirt collar and glancing down to see how much her nipples were pebbling.
