A form of nipple torture, which can lead to changes or lengthening of the nipple, is stretching. This is where the nipple is deliberately pulled outwards from the chest, elongating it. There are a few ways this can be done.
One way is to use nipple piercings such as barbells. By winding string or cord between the areola and the piercing, the piercing is pushed outward and stretches the nipple. The more cord you wind the more the nipple is stretched. This is a fairly mild form of torture but you do need to be careful that you don’t stretch so much that the piercing tears out. One advantage of this technique is that because the nipple isn’t being clamped, and so long as you don’t wind the cord tightly, there won’t be a blood circulation problem and the cord can be left in place for extended periods. As the nipple stretches over time you can keep winding on more cord, stretching it even further.
A more painful form of nipple stretching can be performed using nipple stretching frame and it is most easily used on a submissive who is lying on her back. The base of the frame is placed on the submissive’s upper chest, just above her breasts. The clamps are then attached to each nipple and the crossbar is lifted up until the nipples are stretched sufficiently. The crossbar is then locked in place.
Another way to stretch nipples is to use weights. This was also mentioned earlier. By tying a submissive so that she is leaning forward, attaching clamps to her nipples, and then attaching weights to the clamps, her nipples can be tightly stretched downwards.