Lyric discussion by autumnsoliloquy 

Cover art for Mosquito lyrics by Ingrid Michaelson

I don't think it's necessarily about sex. It's more about the speaker knowing that she shouldn't taste a forbidden fruit but still wants it anyway, even though it's poisonous, e.g. a relationship that is possessive-obsessive, but she loves it being desired even though it may hurt her sometimes. Just my two cents.

My Interpretation