Aug. 15 (UPI) -- Sophie Turner is opening up about what it was like kissing her former Game of Thrones co-star Kit Harington in the upcoming gothic horror film The Dreadful, which Turner also produces.

The actress, 29, and Harington, 38, played onscreen siblings Sansa Stark and Jon Snow on Game of Thrones and now portray lovers in The Dreadful.

Turner discussed the film on Late Night with Seth Meyers Thursday.

"I sent the script to Kit and he kind of sent me a message back going like, 'Yeah, I'd love to, but this is going to be really ... weird Soph,'" she told Meyers. "And I was like, 'What is he talking about?' And then I was reading it and I'm like kiss, kiss, sex, kiss, sex. And then I'm like, 'Oh, shoot, that's my brother.'"

"But it's such a good script that he was like, 'We kind of have to do it.' So then we put it out our minds and then we get on set, and it's the first kissing scene, and we are both retching. Like, really, it is vile. It was the worst. Another really bad moment in my career," she added.