11 Reasons Why Filming Sex Scenes Is Really Unsexy, According to Celebs

The eye-catching love scenes in Fifty Shades Freed may look sexy, but filming them was just the opposite for Dakota Johnson. "It's never easy," the actress told Marie Claire of filming sex scenes with costar Jamie Dornan. "It's not casual and it's not fun." Part of that challenge might have to do with the fact that she had to wear strapless thongs that covered her unmentionables — undergarments that needed to be superglued to her body. "I had these sort of strapless thongs that had glue on them. It's not glue, but it's sticky. They’re, like, basically if it were a nipple pastie, but underwear. But it’s only sticky at the top, it’s not sticky the whole way," she said. "It would also come off because the adhesive would wear out, so then they would superglue it to my body so that it wouldn’t fall off. And I would wear two of them."

Rosamund Pike and Neil Patrick Harris certainly left an impression on audiences with their violent scene in the 2014 thriller, and rehearsing it was no less memorable. "When you're actually shooting it and you've got a whole crew around you it's remarkably normal," Pike shared on Late Night with Seth Meyers. "However, the odd thing that [director David Fincher] asked us to do was rehearse this scene for two hours, alone, on an empty soundstage — just Neil and myself. And that is when it feels highly inappropriate. You're alone with a man who's not your husband who also has a husband. He's in his underwear, you're in your underwear and you're sort of dry humping on a bed."

"So then we think, 'Okay, we should be professional about this. We should probably film it on an iPhone and sort of see how it looks,'" she continued. "We watch this thing back and it looks like we're making some sort of super creepy home porn movie."

One of Justin Timberlake's least favorite parts of acting? Shooting sex scenes, which he did plenty of with Friends with Benefits costar Mila Kunis. "It's actually kind of annoying, you're there for 12 hours, it's exhausting," Timberlake told BBC Newsbeat.

"I just start by apologizing," the actor said when asked about shooting sex scenes. "It’s like ... you sort of try to set some ground rules and apologize for like ... I always use Sir Laurence. When in doubt, use Sir Laurence Olivier. I think he said something to the effect of, ‘I apologize if I get aroused and I apologized if I do not get aroused.'"

"There is always a particularly large and hairy man holding a boom wearing a crop top," joked Olivia Wilde of filming sex scenes, in a 2009 interview. "I don't know if they're like, 'Ooh, sex scene, where's my crop top because I need to hover above Olivia, make sure my hairy belly is somewhere in the vicinity of her face.' People imagine it's this really glamorous and sexy thing, but I always laugh because in reality there are 50 people in the room. You are stopping and starting. There is someone yelling, like, 'Can you move your hand, can you just put your shoulder down, OK, good, more, more …'"

The Americans costars — and IRL couple — Matthew Rhys and Keri Russell opened up to The Hollywood Reporter about whether or not sex scenes are less awkward with your real partner. "There's that immediate thing where, like, physically you're comfortable together, and so that's fine," Rhys said. Although there's more physical comfort, the actor did admit that it's a little weird to have his actual girlfriend so exposed in front of the crew. "I get a little protective. I'm like, 'Can someone get her a f------' robe, please?! She's standing there naked, we've cut for five seconds, Jesus Christ.' And they're like, 'Dude, this is the fourth season,' " he joked.

Natalie Portman recommended that director Darren Aronofsky consider her friend Mila Kunis to join her in the Black Swan cast, but didn't consider the fact that it would mean they'd be sharing a sex scene.

"I didn't really think through the fact that I was going to have to have sex with her in the movie," she told MTV News. "It was pretty awkward. I almost feel like it would be easier to do it with someone you didn't know. But, having said that, it was great to have a friend there who, we could laugh and make jokes and get over it together."

The actress managed to keep any cringing from making it on-screen, and went on the win the Best Actress Oscar for her role.

"The hardest thing about sex scenes is that everybody is a judge," Michael Douglas said when talking about his one-take sex scene in 2014's Behind the Candelabra. "I don't know the last time you murdered somebody or blew anyone's brains out, but everyone has had sex and probably this morning, which means everyone has an opinion on how it should be done."

Charlie Hunnam has stripped down for the camera plenty of times, but he secretly hates having to film sex scenes for two very important reasons: His girlfriend, Morgana McNelis, doesn't enjoy watching him with other women and, well, they gross him out. "I try to be sensitive to the fact that we're doing something intimate, but also keep a clear boundary. Because I'm in a very committed relationship, and I'm also cognizant that it's not my girlfriend's favorite part of my job. It's a delicate balance to strike," he told ELLE. "I'm also a germophobe. I’ve been profoundly germophobic since I was a young child. I don't want to kiss anyone but my girlfriend for my whole life."

When it came time to rehearse for her sex scene with costar Woody Harrelson for their film, Wilson, Judy Greer made it a point to get into it. "I'm gonna really do my full performance here for this rehearsal so everyone knows what I'm gonna do," Greer recalled to PEOPLE of how she hyped herself up for the scene.

But as Greer quickly found out, she might have gotten herself a little too hyped. After the rehearsal, the film's director, Craig Johnson, walked over to her and cautioned, "I don't think she's that into it."

"And I was like, 'Oh my gosh, never again,' " Greer said. "I'm so embarrassed. I'm so mortified."

"In the scene, she's sitting there and I take her top off and the bra off, and she has those pasties on, but she's drawn these adorable little smiley faces on them," Reynolds explained on The Tonight Show of filming with his The Change-Up costar Olivia Wilde. "And I forget every line in the scene—not just from this movie but from every other movie I've done."