Behind the digital mask: semi-anonymity and user self-disclosure in the Momo phenomenon on Xiaohongshu

In contemporary society, where digitalization has fully permeated, social media has profoundly reshaped the fundamental paradigms of information dissemination and interpersonal interaction. However, with the strengthening of panoramic prison surveillance and the dissolution of online privacy boundaries, users are facing an unprecedented tension between pursuing social connections and safeguarding personal privacy. Against this backdrop, the Momo phenomenon emerged on the Xiaohongshu platform, where many users voluntarily adopted uniform pink dinosaur avatars and nicknames, forming a large, semi-anonymous group and becoming a unique cultural landscape and social practice. This study aims to deeply analyze the Momo phenomenon on the Xiaohongshu platform through a literature review and theoretical analysis, and to explore how anonymity changes users' risk-perception structure and thereby motivates their self-disclosure behaviour. Based on the Privacy Calculus Model, the research reveals that by adopting standardized identities, users effectively reduce the social risks and psychological costs of self-disclosure, making the benefits of a sense of security and belonging exceed the potential costs of privacy leakage. Meanwhile, the Social Identity Model of Deindividuation Effects (SIDE) explains the high degree of collective identity and behavioral consistency exhibited by this group in specific situations: deindividuation does not lead to simple disorder but rather prompts individuals to shift from personal identity to group identity. This mechanism is a double-edged sword. It not only provides a haven for marginal viewpoints and emotional venting but may also induce group polarization and cyber violence through moral disengagement.