The popularity of Taylor Swift has been growing rapidly on social media after the release of her ‘Midnights’ album on 21 October 2022. The lead single of the album, ‘Anti- Hero’ and the ‘Anti-Hero Challenge’ initiated by the singer inspired 17 thousand fans (Swifties) to share their own anti-heroic stories inspired by the song. The aim of the study is to examine the contribution of the Swifties online fan community to the ‘Anti-Hero Challenge’ on YouTube Shorts. The research interests revolve around Swifties’ prosumption practices in a dialogical relationship with the original music media material, the fan community, the platform, and the artist. The goal of the analysis is to demonstrate how Swifties use YouTube Shorts for both personal and communal expression by means of prosumption. Prosumption refers to the synchronous production and consumption of media content in the field of Media and Communication Studies (Zajc 2015:29). The thesis illustrates how online performances, interactions, and discussions nurtured by prosumption practices shape and maintain the Swifties fan community on YouTube Shorts. The study applies the Uses and Gratifications Theory and Netnography to scrutinize how Swifties reuse Taylor Swift’s song ‘Anti-Hero’ to make their own media products, and give each other feedback. The findings indicate that online fan prosumption and discussion practices not only foster entertaining, humorous, creative, and challenging self-expression but also provide pathways for communal exchange.  Swifties fan community members play a dual role in not only being active audiences and critics of ‘Anti-Hero’ but also of fellow fan prosumers. Swiftie prosumers and commenters of the ‘Anti-Hero Challenge’ videos also draw attention to controversial societal problems and call for change. The findings indicate the beginning of an era where the boundaries between music production and consumption dissolve. The thesis calls for further scientific inquiry into music fan communities’ prosumption practices online and offline.