Hi, sorry. Haven't read the whole thread or earlier threads on the subject but first, my two cents. A big YES to cunnilingus in general. I was in a relationship with a bi woman who didn't allow anyone to go down on her, men or women, but loved servicing her partners this way. She wouldn't discuss it so I am not sure the reasoning. She was fine exposing her beautiful pussy, having it fingered, fucking etc. Just not oral performed on her. Granted for a lover of the practice, it was frustrating. But we all must respect each other's limits.
Back to the original question...how does one truly answer that. I've asked my bi female lovers and their lovers how do they define sex...they have said, "Between two women it is sexual touching, rubbing, fingering, oral, toys...all is sex...but with men, for some reason we haven't fucked unless his cock in in my pussy." Does this make sense? It's like who said you blue jeans go with anything but blue slacks don't match every color? This is why I like the lack of definition. Base attraction not on linguistics, semantics, others' rules and perceptions but on what feels good for you.
We spend half of our lives thinking about silly things instead of acting and reacting with our hearts and instincts. Know yourself and the trust yourself. Don't categorize it. Ask for it. Volunteer it. Bury your face in the moment and JUST DO IT!
Quit defining and get naked, for heaven's sake. Who cares what percentage of straight/gay/left/right/black/white someone is...are you turned on? Make a move! Let someone know you are attracted, that they're sexy that you love them any way they want, in any order they want. Give more love than you get and more will come your way. Life is foreplay. Don't miss it.