First, this article will establish a methodological framework for its genre study of UF/PR. Next, the article will critique several extant approaches to this genre. It will then offer my own original and complementary genre history and definition. Most significantly, this article argues UF/PR is defined in part by generic hybridity. It further argues that UF/PR is both formally and thematically concerned with destabilising boundaries – boundaries of genre, of media, of self and the monstrous Other. Finally, the article will conclude that understanding how UF/PR transgresses the boundaries of both genre and media is crucial to understanding its current popularity and commercial success.