Book Recommendation: Boys' Love Manga (even includes girlfags and guydykes in the last essay!)
I just finished reading Boys' Love Manga: Essays on the Sexual Ambiguity and Cross-Cultural Fandom of the Genre (it's available to buy digitally and physically on Amazon; one can find out if itis in a nearby library on Worldcat). It has been awhile since I've read / looked at yaoi, but the title and the academic bent caught my eye, so I gave this one a go. If you can get past the over-the-top scholarly language of a few of the essays in the book ("Lacan"-this, "topos"-that), there is much material of interest to girlfags and those with similar identities, whether you are familiar with boys' love (BL) / shounen-ai / yaoi manga or not. Fan and author accounts of interest and creativity collide with academic theory here, and not always neatly (which is part of the fun). Many of the authors in the book easily see the queering of otherwise seen as straight women's sexuality and gender expression that is facilitated through reading and creating yaoi and related inspired works, and Western slash fanfiction is a not infrequent point of comparison.
The last essay even mentions girlfags and guydykes specifically: 'Hidden in Straight Sight: Trans*gressing Gender and Sexuality via BL' by Uli Meyer. Girlfags and transgender men who are gay (also known here as transfags) are seen as on a kind of continuum where the difference is one of degree (from simultaneous identification as a girl and as/with gay men to no identification to being wholly identified as a gay man, even seeking transition). I know of a girlfag or two, and a transman or two, who would have a bone to pick with this description for various reasons, but it may be helpful as a means of self-definition / understanding for those of us who first identified as girlfags, and then decided that genderqueer, transgender, FTM, or other terms were more appropriate instead of or in addition to girlfag (or vice versa). Meyer speaks of the importance in community-forming amongst gender and sexual minorities (the GirlFags Yahoo group is mentioned here). Later in the essay, guydykes and transdykes are mentioned in a passage about cosplaying and lesbian identification. Much of the essay is devoted to articulating the way that queer gender and sexuality possibilities are explored through yaoi and the fandom activities that derive from it.