Consider Big Mouth the bildungsroman for bodily functions — the series is about the spiritual awakening of the hormonal glands, the eruption of all things gross and embarrassing. Nick Kroll voices Nick, a prepubescent boy struggling with the fact that his best friend Andrew (voiced by John Mulaney) has already hit puberty. In Big Mouth, puberty comes in the form of the "hormone monster," a sex-obsessed puberty Virgil of sorts. He's there to guide the boys through the horrors (and the joys) of puberty. (Kroll also lends his voice to the hormone monster, as well as several other characters.)