Gavin Leatherwood wants to make it “abundantly clear” that he’s dating his Sabrina co-star Luke Cook. The American actor, who plays Nicholas Scratch on the critically-acclaimed Netflix fantasy series, addressed the rumours on Twitter with a picture of him and Cook – who plays the Dark Lord – cosied up together on the sofa. “Just to make it abundantly clear… @lukecoook and I are and have been dating for over a year now.