This article explores the relationship between friendship, personhood, and ethics among girls in a London school. While a Western ideal of friendship is posited as a personal, private, and spontaneous relationship between autonomous individuals, I argue that girls’ friendships are a complex entanglement and interaction between forensic and mimetic dimensions of the self. Girls’ ideals of friendship, and practices of making friends, suggest forensic pre‐constituted selves acting with volition in order to become closer to other selves. However, bitching, exclusion, and breaking friendships foreground mimetic dimensions as girls shape each other and themselves according to gendered ethical criteria. Examining these analytical strands offers insight into how individuality is produced through sociality in everyday life.