As seen in: Boa vs. Python (2004)
In the most imaginative interpretation of the "David Blaine" sex maneuver we've ever seen represented in film, we're made privy to an intimate moment between an award-winningly oblivious girlfriend and her man, who's attacked by an enormous snake and pulled from the car while he's in the middle of going down on her. With her eyes closed, concentrating on the sensations below, she fails to notice that "Brian" has become reptile food—or that the massive python has slipped into the car and taken his place.
Amazingly enough, the snake's skills appeared to exceed her boyfriend's; the woman's moans in response to the new Brian were all kinds of loud, at least until she took a look down to admire her pleasurer. Rough.