There are a number of gaps in current understandings of the links between young femininities, agency and social class. Building on recent work, we examine how closely young middle-class women in one fee-paying school in England take up so-called top girl discourses and explore whether and how such discursive positions are linked to agentic practice within sexual and intimate relationships. Only one young woman in our study appeared to relatively successfully embody the idea of a ‘top girl’ and, through the use of an ‘I am powerful’ narrative voice, appeared also to demonstrate the most sustained, agentic approach to her sexual and intimate relationships, as well as many other parts of her life. Although other young women also drew on this idea of themselves as powerful, their narratives demonstrated fewer moments of agency, largely because they desired equally confident, assertive men as their partners (whom they understood would be dominant to them).