Cosmetic technique whereby strong bleaching solutions like hydroquinones are used to lighten the anal area. This procedure is employed by strippers, body builders, actors and actresses. Seems over time, the butticular area becomes darker (some say it's due to dark foods like coffee, others speculate it's due to staining from the bilirubin content in feces.) Either way, those who aspire to wear butt floss as swimwear or do pole dancing seem to feel a lighter sphincter will improve their image.
The treatment is said to sting quite a bit.