["Journal of Personality, EarlyView. ", "\nABSTRACT\n\nObjective\n“Simps” are individuals (primarily men) who engage in costly or extravagant gestures toward a romantic interest without receiving reciprocation. As its first empirical validation, the current study newly operationalizes simping behaviors as well as the motivating factors predicting simping.\n\n\nMethod\nAct nomination and act frequency designs (Total N = 415) were used to identify the defining behaviors of simps. Correlational (N = 200) and experimental designs (N = 584) were then employed to examine effects of the fear of being single on simping.\n\n\nResults\nAcross three studies, we found that simps were perceived as low in mate value, lacking self‐identity, engaging in excessive and obsessive pursuit behaviors, as well as exhibiting exploitative tendencies. Furthermore, participants with greater fears of being single reported greater tendencies of simping behaviors, and when individuals were primed with the fear of being single, they reported greater tendencies to engage in simping behaviors. Predictors including mate value, social status, and social dominance did not predict simping behaviors.\n\n\nConclusion\nThe fear of being single contributes significantly to the motivation behind male simping behaviors. We posit that the current precursory findings carry evolutionary (mal)adaptive implications concerning mate selection that are ripe for future avenues of research.\n\n"]