
The actor, who played Spike in Buffy The Vampire Slayer and Angel, said his partner had a long-running fantasy that he would kiss another man.
Marsters guest stars as bisexual Captain John in the second series of the Doctor Who spin-off, and filmed the smooch with his co-star over the summer.
He said: "I had never kissed a man on film before, but luckily my girlfriend was there, and she said it was always a fantasy of hers that I would kiss another man. She thought it was really hot."
Barrowman, who is openly homosexual, recently described gay stars who refuse to come out of the closet as "sad".
> Click here for our interview with Russell T Davies and members of the Torchwood cast






