Abstract: The energy metabolism level and personality traits of animal individuals may significantly affect their physiological requirements and behavioral strategies, making them key determinants of companion selection in social interactions. The juvenile Chindongo demasoni was selected as the experimental subjects to investigate how similarity in energy metabolism (routine metabolic rate, RMR; maximum metabolic rate, MMR) and personality traits (activity, aggression, and sociability) influences social proximity and preference. Additionally, the relationship between energy metabolism and personality traits was analyzed. The results showed no significant correlation between energy metabolism and personality traits in C. demasoni. However, individuals with greater differences in MMR exhibited higher social proximity (P=0.005), with high-metabolism tending to choose low-metabolism as social partners. Moreover, individuals with similar levels of aggression were more likely to stay close to each other (P<0.001). The tendency of high-metabolism individuals selecting low-metabolism companions may represent an adaptive strategy to balance group-living benefits with reduced intraspecific competition. Meanwhile, the stronger spatial proximity tendency observed in individuals with similar aggression levels may be related to the species’ strict social hierarchy, where similar aggression levels need to engage in direct confrontations to establish dominance. These findings suggest that energy metabolism and personality traits are largely independent in Chindongo demasoni but both shape companion selection during social interactions. Intraspecific competition appears critical in molding fish social interactions, highlighting the complex interplay between metabolic physiology and behavioral ecology.