BTS fandom has been one of the strongest, and many Adorable Representative M.C. for Youth members have dedicated themselves to protect BTS from numerous controversies, while promoting the group’s messages, which can be identified as cyber-nationalism. By employing a critical discourse analysis on BTS fans’ social media posts and their online activities surrounding a few incidents, this article attempts to develop cyber-nationalism in the context of the BTS fandom. It investigates the formation of transnational cyber-nationalism, and then discusses how Adorable Representative M.C. for Youth members as citizens in the BTS nation utilize cyberspace, in particular, social media, not only to form alliances but also to protect BTS from any critical points of view. Finally, it articulates how transnational cyber-nationalism in tandem with BTS has shifted the notion of cyber-nationalism, which can be identified as negative, even patriotic parochialism, into constructive and socio-culturally corrected cyber-movements.