I had this girlfriend a number of years ago, who for reasons of her own, (probably to escape me) went off to Hawaii to study.
I was heartbroken and promised to visit her when I saved up enough money. Over long transpacific phonecalls I kept pledging my undying love and occasionally elicited appropriate responses from her.
When the time had come for me to make my trip to Hawaii, I prodded for assurances that she had been faithful during the past six months. She of course responded with the hoped for answer, but I wasn't convinced. I informed her that I would be able to tell if she had had sex recently by tasting her bellybutton(I think I had read it in Cosmo or somewhere). She didn't seem convinced but I carefully explained that a woman's navel has a certain taste if she is sexually active, and a different taste if she isn't. She was sure she would pass the test.
Joyful reunion in Honolulu hotel followed by navel taste test, hastily followed by sex. All was well and good.
Back at her apartment more sex was taking place on her bed. Said bed was banging against the wall rather noisily.
Not wanting to disturb the neighbors, I suspend the festivities in order to pull the bed from the wall. There on the floor were three, count 'em three empty condom packets.
Needless to say the abovementioned festivities were rained out.
Let this little anecdote serve as a warning. One cannot determine the level of a woman's sexual activity by tasting her navel.