Nipple or breast stimulation is a common human sexual practice, either by itself or as part of other sexual activities. The practice may be performed upon, or by, people of any gender or sexual orientation. Adult women and men report that having their breasts and nipples stimulated can both initiate and enhance sexual arousal.
Regardless of size, all breasts have the same number of nerve endings. Accordingly, smaller breasts are more sensitive while larger breasts may require more intense stimulation. Breasts, and especially the nipples, have heightened sensitivity and are highly erogenous zones for both men and women. Proper stimulation of which may produce sexual excitement and possibly even orgasm.