"My guy pretty like a girl. And he got fight stories to tell," Frank Ocean sings on his new single. "I see both sides like Chanel."Ocean is one of a growing number people—albeit, probably the one with the highest profile—who in recent years have begun to publicly resist strict labels on their sexuality. It could also explain why, especially among students in my human sexuality classes, one of the most frequent questions I get is on the topic of sexual fluidity. Thanks in part to celebrities like Ocean—not to mention Miley Cyrus , who identifies as pansexual, and Kristen Stewart, who has said that she's bisexual but also declared herself "so gay " on a recent Saturday Night Live episode, sexual fluidity is having a moment.And what I've found is that people are intrigued, but also confused. So, what exactly does it mean to be sexually fluid? Let's start with the basics: The term first gained widespread popularity after the publication of a 2008 book, Sexual Fluidity: Understanding Women's Love and Desire , by the researcher Lisa Diamond, a psychologist at the University of Utah.Continue reading on Tonic.