Lol, I didn't watch that BTS stuff people talking about in this thread but your description matches what I read from a director interview back then. It was about eels and octopus insertion genre where the actress also appears to be r***ing. The director says that actually all performers (male and female) and crew members have great relationship off screen and they eat the animals together after they are done filming lol.
This is why I still prefer movies where they use semi- or real amateur male performers, preferably with less acting as possible and just do a huge orgy (like the old and venerable MOODYZ Camp Fan Appreciation series), because what you see on screen is not that far from reality. This is also where they can freely show the crew members filming.