longbough

While the anus is full of bacteria and ass-to-mouth presents some degree of risk - it's surprisingly not as extreme a risk as people tend to assume. It certainly not FORBIDDINGLY risky.

Medically speaking, the mouth (and whole digestive tract for that matter) is considered external to the body, believe it or not. As such it has a whole bunch of defense mechanisms (e.g. gastric acid and digestive juices) as well as a well-described network of lymph nodes along the digestive tract. In fact your digestive system is home to many bacteria already. Most of the bacteria in fecal material came from the digestive tract to begin with.

Now I wouldn't advise eating shit on a regular basis because there is a threshold on how much your digestive system can handle at once - but, unless someone has hepatitis, dysentery, cholera, rotavirus, c. difficile or some other transmissible illness one really one shouldn't worry as much about ass-to-mouth. While I couldn't class it as a sterile practice - but neither is rubbing your eye with an unwashed hand. And, as with all sexual practice, basic laws of hygiene ought to apply as well (e.g. bathe).

I repeat: Your mouth and digestive tract are considered external to the body.

That's why people don't drop dead from rimming.

Trust me, I'm a doctor.

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"I do believe that, where there is only a choice between cowardice and violence, I would advise violence. Thus when my eldest son asked me what he should have done, had he been present when I was almost fatally assaulted in 1908, whether he should have run away and seen me killed or whether he should have used his physical force which he could and wanted to use, and defended me, I told him that it was his duty to defend me even by using violence." - Mahatma Ghandi