This study examines the role and impact of Weibo marketing accounts using the "Wang Xiaofei and Barbie Hsu (Da S) Incident" as a case study. It begins by defining Weibo marketing accounts, highlighting their active engagement in trending topics and their content patterns. Using a model of public opinion formation, the study explores how these accounts influence public discourse from inception to consensus formation stages. Analysis of both the propagation effects (such as amplification, catalysis, and fission) and operational effects (influencing behavior, changing perceptions, and stimulating further exploration) reveals the significant impact of these accounts on information dissemination and public opinion on Weibo.