GURL sounds Vs. BOY sounds...(no fiting in the house, please.)

so, there we were, listening to basement jaxx's rooty when nancy up and sez "who is this?" i figured i had played it enough times to be known, so i said - somewhat incredulously - "it's basement jaxx." "oh really?," she replied, "it sounds much more 'girl' than anything else i've heard by them." (the song was the downtempo one right before "i want u" that i cant remember the name of, btw.) confused, i tried to press out what she meant, but there was no prying. i played each successive track, trying to gauge whether or not this was just some silly "girls like pretty tinkly sounds" thing. (not that i think my girlfriend is silly mind you, just that i am naturally skeptical of all theories of pop except my own.) i was proved wrong when she said that "get me off" (obstensibly the nastiest sounding song of the album) was resoundingly "girl." i have been trying to get her to explain this for weeks, and it becomes more thorny with every turn (some piano magic is "girl" when it was composed by a man, but maxwell's cover of the kate bush song is still "boy.") the most i have been able to get out of her is that it may have "something to do with space, notes, and the placement of notes."