comment on slash fan fiction

When reading slash fiction, I think one would first assume it to be written by a male homosexual. It seems to be written for the purpose of extending preexisting characters into an extended world in which they take on homosexual identities that they wouldnt normally take on in their original setting (film, tv show, etc.). This allows fans to bring the characters into their own world, and share cultural similarities with the characters, that people of the heterosexual culture can already do. ..When I read more on slash fiction on wikipedia, it said most slash fiction is written by women (whether this is true or not, of course I dont know for sure), but i found this very surprising. I dont entirely understand the reasons for a heterosexual woman, who is the fan of something, to take its characters and place them in a homosexual sex scene, unless they are just playing with gender roles through their this free creative space. I would really need to research more on the motives of the authors of such fan fiction to really understand it. (especially between male and female authors)