I don't know i haven't heard it. Also they are breathing/moaning heavy. Moving around on furniture and obviously the sounds of the body's grinding together. Are you sure that it is THAT sound? And which time stamp?
At some point during the scene when Samya was on top of him, you could hear an audible "queef" sound. No way the sound department edited that in. Check it out, get yourself a half-decent headphones and listen carefully to the sounds they make during the scene. Thankfully there's no stupid music ruining it.