When me and my girlfriend have sex, (pussy) doggy style i always get a whiff of the anal region. Does this always happen, can it be avoided or is it just bad hygene?!
a bit of vicks vapo rub under your nose and you should have no problem tapping even the nastiest skank....sometimes I find it necessary when dating homeless girls
Are you sure your not being just paranoid? Just coz you can see the brown hole doesn't mean it stinks!! Might just be in your head, but a shower before sex is a good idea, maybe join her in the shower and have some fun, then gently slide a soapy finger up her ass..... Then throw her down on the bed and fuck her doggie and see it that changes anything!! If not go with "Rollingalong" idea and use a little bit of Vicks vapo rub!
She is not cleaning there when showering or has BM issues, intestinal and is leaky, which could mean health issues or bad diet. A good wiping after BM and proper showers should mean no smell ever I think. Or, it is in your mind because you see it. Dunno.
Any area on the human body that contains glands will have some sort of odour at any given time. Not necessarily a bad or a good odour. Just, odour. The respectful approach would be to suggest a mutual shower beforehand, in a way that implies it's part of the sensuality and not you subliminally say, "honey, your crotch stinks." I think most women are aware of the scents their body can give off. As should men be of their own. You can also pick up some feminine wipes and go for a more straight forward approach. If you know each other well and you're polite about it, it should be fine.
You may be partly paranoid as mentioned Your G/f may be a bit lax hygeine-wise. the fact is even the cleanest botty is never totally odor free, and many people find it a mental aphrodisiac.
shine a light in her window at 2 in the morning, thats sure to scare the crap out of her....then when the craps all gone your good to go.