Do we really need sex scenes in films? Like, yes, they add some excitement and propel the story and show how well characters are getting to know one another, but do filmmakers know how uncomfortable it is to watch two characters get it on while sitting in complete silence with parents next to you on the couch? Plus, it turns out that they're really difficult to film. Actors have to awkwardly pretend to get intimate with colleagues, and there are a bunch of protocols in place to keep things decent which are way less sexy than they are on screen. These 10 actors have revealed behind-the-scenes details about famous sex scenes they've starred in, and boy do they sound wild – but not in a good way. 1. Christopher Mintz-Plasse was required to have a very unwelcomed guest on set while filming Superbad The McLovin actor was only 17 at the time, meaning his mother had to be there. "She got there, and I had fake sexual intercourse in front of her," Mintz-Plasse told GQ. "Afterwards we didn't talk about it; we still don't speak about that moment." 2. Margot Robbie says that having fake sex with Leo on a bed of money was really painful in the Wolf of Wall Street "I got a million paper cuts on my back from all that money! It's not as glamorous as it sounds," she told the Daily Beast. "If anyone is ever planning on having sex on top of a pile of cash: don't. Or maybe real money is a bit softer, but the fake money is like paper, and when I got up off the bed, I turned around to get my robe and everyone gasped. I said, 'What is it?' And they said, 'You look like you've been whipped a million times. Your back is covered in a thousand red scratches." 3. Ryan Reynolds was literally speechless in a sex scene with Olivia Wilde in The Change-Up "So in the scene she's sitting there, and I take her top off, I take her bra off, and she has those panties on, but she's drawn these adorable little smiley faces on them," he revealed on the Tonight Show With Jay Leno. "And I forget every line in the scene. Not just from this movie, from every movie I've done. At some point in the scene, she takes my hands and puts them on her breasts. I take my hands away, and I look down at my hands, and there are two frickin' smiley faces on them and I have no idea what to do. And I reflexively, like an idiot, just put my hands right back on her breasts!" 4. <a href="http://vt.co/entertainment/film-tv/emilia-clarke-shares-true-feelings-nudity-game-thrones/">Emilia Clarke</a> was totally enchanted by Jason Momoa's "modesty sock" in Game of Thrones Momoa, AKA Khal Drogo, decided to upgrade the "modesty sock" he had to wear by using a bright pink fluffy one: "It's huge, and it's pink, and I don't know what to do!" she told Graham Norton. [[youtubewidget||https://www.youtube.com/watch?v=IIBLYfeGxYY]] 5. Jon Hamm also felt kind of weird about his cover-up on Bridesmaids "There's an awkwardness about being in a weird flesh-coloured thong, bouncing on top of an actress," he told Playboy. "And I am not a small human being. I weigh at least 200 pounds and I'm six-foot-two. And Wiig is a twig; she's a skinny little thing. I told her, 'Just punch me in the side if I'm hurting you.'" 6. <a href="http://vt.co/entertainment/celebrity/jennifer-lawrence-fires-back-backlash-revealing-dress/">Jennifer Lawrence</a> needed some Dutch courage on Passengers "I was like, 'Oh, I'm gonna get hammered for the sex scene,' because it's stressful and scary," Lawrence told Seth Meyers, "And then you forget you're at work, so you're gonna be there for eight hours. I was incredibly hungover by the time they got to me." [[youtubewidget||https://www.youtube.com/watch?v=Bt5WzvTvspU]] 7. <a href="http://vt.co/entertainment/celebrity/heres-shouldnt-approach-jamie-dornan-public/">Jamie Dornan</a> reveals that those Fifty Shades of Grey scenes really aren't that sexy He said on Jimmy Kimmel Live that he had to wear a "wee bag" to avoid penetration, and that upon closer inspection, the bag had "Inmate #3" printed inside it, indicating it had been used before... [[facebookwidget||https://www.youtube.com/watch?v=pGgTkFKfLXE]] 8. Dakota Johnson also agrees that the Fifty Shades scenes were less than erotic to film She told Marie Claire that she had a modesty thong superglued to her body, that there was a sex advisor on set to tell them off if they weren't using the toys and S&M equipment properly, and that she would "have a shot of something strong" before particularly difficult scenes. 9. Kate Winslet felt like a complete different person during that steamy hand-down-the-window scene in Titanic  "Doing that scene — it so wasn't us," she told Rolling Stone about doing the scene with co-star Leonardo DiCaprio. "And yet we were so locked into what all that had to be about. The Rose in me was really sort of loving the Jack in him, actually. And even though I didn't feel that way about Leo, it was quite nice to sort of feel that way in the scene. It was quite lovely. And then, y'know, the camera stopped rolling, and he gets up and walks off, and the scene's done. And I remember lying there thinking, 'What a shame that's over.' Because it was quite nice. It was." 10. Henry Cavill couldn't hide that he was into it on The Tudors "A girl had to be on top of me, she had spectacular breasts, and I hadn't rearranged my stuff into a harmless position. She's basically rubbing herself all over me and, um, it got a bit hard," he told Men's Health. "I had to apologize profusely afterward." Wow, makes you think of those scenes in a whole new way, doesn't it?

10 facts from behind-the-scenes about famous sex scenes that are all sorts of crazy

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