The practice of restraining oneself. This practice usually includes means of sexual stimulation while in bondage, and the participant usually attains a heightened sense of arousal by being unable to pleasure themselves. Sometimes pain is involved, masochisically. Almost always, a release mechanism is used. Whether it is a key in ice, or a timer set to release a key.
Andrea loves to practice self-bondage. Since she can't find anyone else to pleasure her, she ties herself up.