This study is the first to disentangle influencer- and brand engagement and to explore their interplay in shaping consumer purchases, while considering the mediating role of the strength of parasocial relationships (PSRs) between consumers and influencers. The results reveal that while influencer- and brand engagement independently enhance purchases, high brand engagement can diminish influencer engagement’s purchase-enhancing effect through weakened PSRs (representing a “reverse vampire effect”). This negative interplay between influencer- and brand engagement is particularly prominent among the followers of mega influencers, who have millions of followers. High brand engagement can weaken PSRs, particularly with mega influencers, as they may be viewed as manipulative. This research thus provides novel insights into influencer marketing effectiveness, emphasizing the role of PSRs and the need to exercise caution in influencer-brand collaborations, particularly with mega influencers. Overall, this study provides a more realistic understanding of the trade-offs between the benefits and risks of influencer marketing.

2025

forthcoming