Professional actors can perform the most passionate of sex scenes and completely separate themselves from the character they are portraying. Everybody's human though, right?
When I first moved to NYC I got a job in a small film company. I have no idea how, but we got hired on a project for a writer/director who had a few rom-com hits and some TV shows in the 90's and early 00's. This was maybe a year or two after 'Louis' got big, so this director wanted to rekindle his career by doing a show modeled closely after his own life. Now, I'm sure it was someone in my company's job to read through the script before accepting the project, but it became evident to us this person had maybe just skimmed as we found ourselves every day of the shoot shocked at some of the material. The scene I remember the most is one is a BDSM scene. The scene was the actor/director lying is his bathtub being pissed on by a naked dominatrix while he and her also ad-lib a conversation sh_t-talking another, Very Famous Actor. It was meant to come off as humorous. Someone in the crew expressed some vague uncertainty about the legality of us filming the actress, who we knew was an actual dom in real life, actually peeing on him, so we agreed to make a rig with an enema bag and yellow Gatorade. The actress/dom was one of the tallest women I've ever seen and very beautiful. She arrives, is extremely nice, and greets the actor/director very warmly. We start to realize this this woman is his actual, irl dom. Nude scenes are always a bit uncomfortable, but with all of us knowing that we're filming a sexual scene between two people who have an irl sexual history, we were more uncomfortable than usual. We use a stripped down crew for the scene that's just me, two cam-ops, and a PA who is holding lighting equipment and can't actually see what's going on. The actor/director says 'action' and the scene starts. The ad-libbed dialogue between them starts light, and a little awkward but they gradually get more and more into it and the dialogue between them gets more intense. It starts to feel less and less like we're filming a scene and more like we're filming and actual sub/dom session. I realize that I'm unsure if the dom is actually using the fake-piss-rig (the end of which I had essentially gaff-taped to her labia, her idea, not mine), and that she may be actual, irl peeing on him as we film. The crew and I are peak-uncomfortable. The actor/director starts sh_t-talking the Very Famous Actor, to which the dom replies 'OH, YOU LIKE TO TALK SH_T HUH?? YOURE A SH_TTALKER?? MAYBE YOU WANT SOME SH_T IN YOUR MOUTH??' and then begins forcing his face into her bare _ss. As she keeps threatening to sh_t in his mouth as the crew and I are all looking at each other, wide eyed and in horror, with a look that says 'please god, don't let her actually do this'. Moments go by like small eternities. The tiny bathroom we're crammed in seems to be shrinking. The PA who can hear, but not actually see what's going on seems to be wretching a bit. Suddenly, from deep in this woman's _ss the actor/director yells a muffled 'CUT'. He gets up smiling, soaked in yellow Gatorade and possibly piss, and saying 'oh my god that was perfect, that was hilarious, great scene'. I think we all almost passed out from relief. We moved on to the next scene. Maybe the funniest thing about this was that the actor/director was CERTAIN Hulu was gonna scoop the show up. (Source)