And thirdly, they are just more dominant. Sometimes Sarah and her husband notice, when they arrive, a sharp intake of breath. But then sex and relationships are one of the last remaining bastions of unreconstructed racial prejudice. Stereotypes of black and other ethnic minority men as sexually threatening on the one hand, and sexually desirable on the other, are two sides of the same hypersexuality myth. I have a vagina, you have a vagina. When it comes to human relationships, to romance and love and sex, nuance is everything. She decided it was an investment worth making to find a partner who, like her, works in the City and would share her ambition. And I think some black men have bought into the myth that they are hypersexual, that their sexual prowess and the size, the physicality, is greater. They want to feel a strong man inside them, dominating them. We scale a no-frills metal staircase at the end of an alleyway behind the high street, where a weary blond woman is ruling a domain of coats, cash and lists. Miranda is doing much better; she has obediently put on a basque, along with a skirt much shorter than mine, and boots that elongate her long legs. Why are black men willing to embrace the myths of hypersexuality and abnormally large endowment? The problem with these kinds of stereotypes — other than that they originate in racist ideology — is that they both repel and attract people for the wrong reasons.