What happens is usually before hand the female or who ever is receiving the anal, cleans out the anus (usually with a douche or something) then after the 'sex' is preformed you won't notice the feces on the penis or wateva, maybe just a faint discolouration and the feces can get caught behind the glands on the head of the penis. So deffiently make sure you thorughly clean your penis before and after and never use the same condom for anal and vaginal penetration.

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