I've been involved in BDSM for 30 years. The "cleansing" or enema is utterly debasing and humiliating to anyone who has to face it. You are flushed full of not only water, but a liquid stool softener/ laxative called sodium citrate and occasionally aphrodisiacs and stimulants are used. This is like a "super colon blow" and you are subjected to cramps and severe abdominal pain if you try to hold it in. It is usually performed in front of an audience to heighten the humiliation and trust me when I tell you, you can't NOT shit yourself. And you will continue to shit yourself for about an hour. I've seen this performed twice. Once on a new slave who chose their fate and once on a slave who had slept with someone other than their master without permission. Outside of scatology - the seeking of pleasure through feces - enemas like this are usually used as punishment. Severe punishment. You have to understand that things like neglect play, rape play and having pain inflicted is not just an everyday occurrence, it brings pleasure to submissives. So, for a dom or master to really "put their foot down", extreme measures are necessary. Even in BDSM circles scat play and scatology are uncommon. The enjoyment of feces goes against deep rooted fear and revulsion in most people. Thus, something like a public enema is effective for punishment without resorting to inflicting real damage on a person. As for the sub who chose to have it done, once you have shit all over yourself in front of a crowd, there really isn't much worse out there that can embarrass you. This makes things like exhibitionism seem like a picnic in the park.
Could someone who knows about those things tell me more about what's going on in chapter 12 pg 11? I tried google and didn't find anything....