What does it mean to be a boy? To be a girl? Throughout her career, Brooklyn-based photographer Jessica Yatrofsky has been fascinated by how gender manifests. The portraiture in her recent book, I Heart Girl , offers a questioning and playful alternative to the hyper-sexualized standards of femininity imposed on women."It’s digging into how we evolve as human beings, and how we perform our gender, and how we see ourselves in the world at any given time," Yatrofsky tells us. "I wanted to represent the body in a way that was authentic and in line with the way the person was representing themselves" — rather than the ways we have been conditioned to view women, or how women have been trained to present themselves.The resulting photographs mix the "soft" (exposed curves, flowing hair) with the "edgy" (colored hair, tattoos) — though, as Yatrofsky asks, "When are we going to get to a point where we don’t think it’s 'edgy'? It’s just a person expressing themselves how they see fit." We spoke with the photographer about the genesis of the series, her creative process, and the power of sexual performance that's rooted in self-awareness.Click through to read her thoughts and view 13 powerful portraits from I Heart Girl.