Nipple play
The nipples are the part of the breast that is commonly used for this type of activity. Pressure is typically applied to them using nipple clamps or pumps, a type of sex toy which can be attached to erect nipples to pinch them and to restrict the blood flow to them by applying pressure. When nipple clamps are removed, further stimulation is caused by the return of normal blood flow. The nipples involved can belong to persons of any gender.