 Parallels have also been noted in the popularity of lesbianism in pornography, and "yaoi" has been called a form of "female fetishism".Mariko Ōhara, a science fiction writer, has said that she wrote "yaoi" Kirk/Spock fiction as a teen because she could not enjoy "conventional pornography, which had been made for men", and that she had found a "limitless freedom" in "yaoi", much like in science fiction.Other commentators have suggested that more radical gender-political issues underlie BL.