"Bravo Charlie" from the military phonetic alphabet used to transmit letters or code via telephone or radio, stands for "BC," or, in this case, "Beaver Curtains."
"Bravo Charlie" or "Beaver Curtains" (noun pl)
: The vaginal labia majora of female mammals, namely the female homo sapien.
Examples of Bravo Charlie used:
• Hey, Brianna, come near me with that pair of man-scaping scissors and I'm going to kick you in the Bravo Charlie.
• That girl had a Bravo Charlie that I wouldn't touch with your transexual mother's meat sleeve.