In rural China extreme cases of erectile dysfunction are treated with leeches. A leech is attached to the flaccid member for ten minutes. The leech's bite introduces an anticoagulant into the area which greatly increases blood flow. The increased blood flow makes it much easier to achieve an erection. There are three downsides, 1) the threat of disease, 2) a loss of sensation due to the mild anesthetic properites of the leech bite, and 3) the bite tends to bleed copiously for up to a day and a half, longer it the member in question is in heavy use. It is the last downside that tends to cause the most problems. It makes the actual act extremely messy and it sometimes causes lightheadedness when blood loss is added on top of the sensation of orgasm.