Data from Books Ngram Viewer
future, vampires (8)
mutants, post-apocalyptic (6)
fantasy, mutants (5)
future, romance, vampires (4)
fiction, mutants (3)
mutants, science fiction (3)
aliens, romance, vampires (2)
aliens, science fiction, vampires (2)
fantasy, slashy (2)
mutants, --comics, --post-apocalyptic (2)
mutants, --Maximum Ride, --comics, --post-apocalyptic (2)
post-apocalyptic, vampires (2)
1970s, aliens (1)
alternate reality, love (1)
science fiction, --robots (1)
science fiction, -American (1)
science fiction, -Hugo (1)
