In burlesque, a pastie or pasty is something covering and fixed to a female performer's nipple. If the performer is otherwise topless, this may be necessary to avoid indecent exposure. Pasties are often very ornate; for example, they may be covered in rhinestones.
There may be tassels attached to the pasties, and the performer may then move her body rapidly so as to cause the tassels to swing around in circles. Ideally, they should go in opposite directions, one clockwise and the other counterclockwise.