A round, smooth bulge generally found on null characters in place of any specific genitalia. Prevents the wearer from touching themselves, similar to a big soft chastity cage. Often are depicted as being hyper-sensitive and pleasurable to touch while also preventing the character from reaching climax. May be either 'biological' or, frequently, made of latex or rubber.

See also chastity_bulge and lock_bulge, which are similar.