Despite the fun audiences have watching Dornan's Christian Grey and Johnson's Anastasia Steele, filming the sensual moments wasn't almost as pleasing for the actors.
"This is going to sound bad, but it's nearly like brother, sister", Dornan, 35, told ET. Because I am married and [Dakota's] had quite a lot of relationships in the time that we've known each other, so that's happening in our own lives.
"I just don't know how to respond to it because I'm not like him, obviously, so I'm always left panicking and I think they probably think I'm just really weird, which I'm fine with", he said. You just have this sort of mutual love and respect for each other.
The Fifty Shades movies always come out around Valentine's Day - Fifty Shades Freed hits theaters on February 9 - and DeGeneres wonders if this affects how Dornan spends the holiday with his wife, Amelia Warner. "They try to sort of minimize how many people are in there".More news: Confirmed: Asus Zenfone 5 Lineup to Launch at the MWC 2018 Event
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When it comes to his wardrobe, Dornan is set with a "wee-bag", which is an Irish saying for weenie."it doesn't mean it's wee inside". "I wear like, quite a big bag!" "That's the expression I say".
Even less sexy, the wee bag was apparently used by another actor.
Speaking of the sex scenes, the 35-year-old then proceeds to open up about the "wee-bag" he wears while filming to cover up his, you know, junk. I thought you'd take them out of the packets and they'd be brand new; they'd have that brand new smell. "There was a selection of them for me and I picked one", he explained. "Someone was telling me recently that there's more sex in the third one than the other two, but I don't know".