Abstract: Much of the existing research on user aspects in the music information retrieval field tends to focus on general user needs or behavior related to music information seeking, music listening and sharing, or other use of commercial music services. However, we have a limited understanding of the personal and social contexts of music fans who enthusiastically support musicians and are often avid users of commercial music services. In this study, we aim to better understand the contextual complexities surrounding music fans through a case study of the group BTS and its fan community, ARMY. In particular, we are interested in discovering factors that influence the interactions of music fans with music services, especially in the current environment where the prevalence of social media and other tools/technologies influences musical enjoyment. Through virtual ethnography and content analysis, we identified four factors that affect music fans’ interactions with commercial music services: 1) perception of music genres, 2) participatory fandom, 3) desire for agency and transparency, and 4) importance of non-musical factors. The discussion of each aspect is followed by design implications for commercial music services to consider.