Amber Rose and Blac Chyna — This Is How We Do It … Amateur Gynecology

Amber Rose and Blac Chyna let their fingers do a lot more than walking further than a Hollywood nightclub — in fact, we can’t really say what they were doing … because we’re too classy.

The ex-stripper BFFs left the Ludacris album release have fun at Project Club LA and hopped into the same ride … which was apparently so packed they had to lap up — with Amber on top.

We’ll just say they kinda held an impromptu sex ed class for fans and photogs — and everyone paid very accurate attention.

Moms MILFS do the darndest things.