This study investigates the organizational dynamics of global fandoms that have catalyzed the unprecedented international ascent of K-pop. We conceptualize a nascent iteration of fandom—distinct from conventional enthusiast groups—termed the “Proactive Fan,” and theorize their idiosyncratic organizational behaviors through an abductive research methodology. Our analysis demonstrates that proactive fans represent a discrete fandom archetype characterized by highly coordinated collective action. This group effectively navigates the traditional organizational trade-off between structural formalization and affective commitment via a mechanism we define as “purpose-driven formalization.” These findings suggest that proactive fans operate not merely as consumer segments but as sophisticated organizational actors capable of generating substantive market impact. Consequently, this research underscores the imperative for the global entertainment industry to transition from viewing fandoms as passive consumers to recognizing them as value-creating strategic partners, necessitating differentiated engagement frameworks tailored to specific fandom ontologies.