First off, I have no idea what BM means, I assume something in line with Big Mess, or rather, a number 2. I enjoy playing with anal, and I have some internal rhoids, at least that's what my doctor said it was. Often it doesn't hurt or anything, but if I am stressed, pissed at somethnig for prolonged periodes of time, then it might happen. Other times it is just I hear something dribbling during/after taking a dump, and it doesn't even have to be hard/rough. It does turn the water amazingly red tho, but after watching out a bit, I found even a few drops can produce a significant result. All it means for me is that I sometimes have to hold back with anal, take a break, cos I find that doing it anyways it might pinch a bit, which can be a bit uncomfortable, but might also be attributed to me being horny/impatient and not warming up properly. Good thing you ask this question tho, I've heard a lot worse/weirder