Recent research suggests that women react to idealized female models in advertising as they would react to real-life sexual rivals. Across four studies, we investigate the negative consequences of this imaginary competition on consumers' mate-guarding jealousy, indirect aggression, and drive for thinness. A meta-analysis of studies 1–3 shows that women exposed to an idealized model report more mate-guarding jealousy and show increased indirect aggression (i.e., derogation and social exclusion), but do not report a higher desire for thinness. Study 4 replicates these findings and reveals that the main driver of aggression is the sexually provocative attitude of the model (a signal of a flirting behavior and of sexual availability), rather than her thin body size. The ethical implications of these findings for advertising are discussed in light of recent concerns about female bullying, online, and in the workplace.