Villanelle is portrayed as openly bisexual, engaging in sexual encounters with both men and women, while Eve—initially married to a man—questions her attractions and confesses intense feelings toward Villanelle in the finale. This queer tension drives key emotional beats across episodes, including surveillance, close encounters, and the season-ending confrontation where Eve stabs Villanelle amid charged intimacy.

Creator Phoebe Waller-Bridge emphasized complex, transgressive female characters and the sexual nature of obsession, aligning with feminist themes of women navigating and subverting male-dominated intelligence work. Casting places an Asian actress in the lead role of Eve (adapted from source novels where her ethnicity is not foregrounded), alongside supporting diversity such as Kirby Howell-Baptiste as colleague Elena, though these elements remain secondary to the thriller plot. The season integrates progressive representation of female agency and non-heteronormative desire as central to character appeal without overt lectures or identity-politics framing as the premise.