The Bangles and The Go-Go's, too.
It's all about Pleasing the Guy
One thing guys can be sure of: chicks up to age 29...to them sex is all about pleasing the guy. Thank god they're wired that way, or we'd have no blowjobs in the Mayfair Market parking lot.
Another funny thing about females: It comes from the rock band touring world. Their cycles get synced to the "alpha female". If they play a gig, then go home in separate cars you don't see this. But if they sleep four to a hotel room, ride around in the van, put makeup together, play together, eat together, then their cycles will happen together too.
They're ANIMALS!