In order to create a transformative work based on canon work, a fan would need to recognize several elements of said canon. One of these elements might not be an inherent part of the transformativeness but it has become a recognizable part of our fannish culture: consent. Fandom is full of non-con or dubcon, of course: not only we have Hydra Trash Party and stormtrooper gangrape, but we have tropes for our beloved OTPs that touch on noncon, such as sex pollen, aliens made them do it or fuck or die. Fandom is also a place where it is the norm to explicitly state any case of non-con/dubcon.
Fuck or die has two prominent examples: Pon Farr and mating, usually in the Omegaverse setting. Milena Popova talks about, in their excellent paper about Omegaverse and consent, why the genre is implicitly conscious of consent issue.
By positing a world with a radically different configuration of genders and sexualities to ours, readers and writers playing in this shared universe can examine gender roles as either driven by the strange biology of the Omegaverse or socially constructed, or a mixture of both. The distance created by the unfamiliar setting enables questions to be asked about the power structures and inequalities around gender, and how they map onto intimate relationships.Popova, Milena 2018. ‘Dogfuck rapeworld’: Omegaverse fanfiction as a critical tool in analyzing the impact of social power structures on intimate relationships and sexual consent, Porn studies