Lyric discussion by dariokosugi 

Cover art for Froot lyrics by Marina and the Diamonds

I think it's pretty much about virginity. She's ready to be deflowered and has waited for too long. Might be because of parents' pressure or whatever, but she is basically feeling really aroused and ready to have sex for the first time. She's eager for it, and demanding a position from the guy she's talking to.

Either that, or just aroused in general. As a feminist, it's also about not caring about what society says about girls: that they should wait for the man to approach them, and can't take the first step. In this song she's defying this social concept by actively telling him that she wants to have it, and she wants now.

My Interpretation