The rise of social media has broken the geographical and communicative boundaries between fans, providing them with a more open platform to express themselves and pursue a shared spiritual resonance. This research focuses on the dynamics and psychological foundations of the BTS Weibo fan community to explore the emotional investment, community connections, and identity construction that arise from the excessive admiration and pursuit of a particular subject, whether virtually or in reality, in the social media era. Based on grounded theory, this research collects data generated by specific fan groups, including their content, interactions, and narratives, and iteratively analyzes and summarizes this data. The study identifies key characteristics of BTS Weibo fan behavior, such as sense of community, exclusivity and gift economy. These findings lay the foundation for further research on the evolving behaviors and motivations of fans, contributing to a broader discussion on media consumption, fan culture, and the psychological impact of online communities.