Another queer horror movie rec: The Hunger (1983)
It has Catherine Deneuve as Miriam, an ancient, powerful vampire, David Bowie as John, her vampire consort, and Susan Sarandon as Sarah, a scientist who stories how aging works. Vampires sure are of interest to her, and she is of interest to vampires.
To be fair, when I started it, I knew it was considered as an erotic movie, so I expected some f/f fanservice in addition to a classic love triangle, and I got something very different and far better than this! The relationship between Miriam and Sarah, a mix of physical attraction, power games and real feelings, might be the most important of the movie!
It's slow, it's weird, but I must confess, none of these things are a problem to me. It's not scientifically very accurate, maybe even for its time. But as soon as we accept vampires, well...
I enjoyed it. It's still horror, so beware!