Almost human? A comparative case study on the social media presence of virtual influencers

•Virtual agents are permeating and interacting on publicly visible human networks.•We compare posting behavior of and user reactions to virtual and human influencers.•The human-like virtual influencer seems to be penalized for her almost human appearance.•Uncanny Valley is seen for positive reactions to the human-like virtual influencer.•A reverse effect is observed for doubt and negative reactions.