Sex robots are likely to play an important role in shaping public understandings of sex and of relations between the sexes in the future. This paper contributes to the larger project of understanding how they will do so by examining the ethics of the “rape” of robots. I argue that the design of realistic female robots that could explicitly refuse consent to sex in order to facilitate rape fantasy would be unethical because sex with robots in these circumstances is a representation of the rape of a woman, which may increase the rate of rape, expresses disrespect for women, and demonstrates a significant character defect. Even when the intention is not to facilitate rape, the design of robots that can explicitly refuse consent is problematic due to the likelihood that some users will experiment with raping them. Designing robots that lack the capacity to explicitly refuse consent may be morally problematic depending on which of two accounts of the representational content of sex with realistic humanoid robots is correct.