. In many group-living primates, males are dominant over females, but despite this dominance, they allow females access to resources during the period when females are sexually attractive - but only then and not otherwise. Conventionally, such male `courtesy' is explained as a special strategy to gain mating access to females. In the present paper I propose a simpler hypothesis that is based on an agent-centered model, namely that male `courtesy' to females is in fact a kind of `timidity' that arises because sexual attraction automatically increases female dominance. The model consists in a homogeneous, virtual world with agents that group and perform dominance interactions. VirtualMales have a higher intensity of aggression and start with a greater capacity to win conflicts than VirtualFemales. I shall explain how the addition of attraction of VirtualMales by VirtualFemales leads to female dominance, and other phenomena that are relevant to the study of animal behaviour. 1 INTRODUCTIO...