Growing up, Brianne attended an all-girls Catholic school, where she was a self-proclaimed "good girl" and where her fellow students weren't nearly as mean as TV shows and movies will lead you to believe. "My school had a lot of cliques, but everyone was wearing the same thing, no one had any makeup on, and no one did their hair. But what was cool is that there was no drama," she told Maxim. "You'd hear stories about other all-girls schools in the area, where girls were hooking up in the bathroom, but I didn't see it. All the drama was on the weekends."
Brianne spent most of her time concentrating on getting good grades in high school, but she also discovered her love of improv during that time. " . . . I think it was there that I kind of found my voice because I was involved in improv and the plays, and I would also do the plays at the all-boy school," she explained during a December 2016 interview with Imagista. "It was just sort of what all the 'cool' girls were doing."