As far as I know, a healthy vag should taste either completely neutral or very, very mild. Gross tastes and fishy smells only occur when a girl has a yeast or bacterial infection, or when her personal hygiene has been poor.
I wouldn't expect a girl to suck my d*ck if it was in awful condition, so no girl should expect me to start lapping away if she's not keeping herself neat. That's my personal philosophy.
But if we're both clean and disease-free, I don't see anything wrong with it. If a girl was giving me head I'd want to reciprocate and doubly so if she's really good at it.
There are always dental dams too, though they're not as convenient to carry around as condoms.
This is something I have thought about the last year. I wonder if its one of those things a woman will fool you with, saying she loves receiving oral to see how much of a dog you will be for her. I remember Tony Soprano never giving his wife oral, seemed alfa at the time. Might be overthinking
Tony Soprano also had an awful relationship with his wife/family, couldn't stop himself banging random trollops and was Alpha to the point of serious insecurity. Remember the time he publically beat the s*** out of one of his younger, more muscular crew members for no reason other than to assert himself? Alpha...but to a mental fault...
As bill said, I don't think it's submissive if you're doing it like a man. If you're mewling and begging to nibble on her, yes, that's pretty lame. If you're eating her like a hungry lion that is not.