Originally Posted by After Shock Media

WTF have you even looked at an anatomy chart?
There is a little shit pocket or holding area about 3-4 inches inside past a sphincter type muscle. Even if your of average size there is a good chance of bumping some doo doo with the tip at least. If you are anything bigger than 6 inches and you are into some full on shit knocking and possibly getting some shit dick suction going on or at least impacting them.

Not to mention anal douching removes any of the fluids/mucus. Everyone has this type of crap even low in their ass. It still has shit in it.