Adam Lyon (voiced by Nika Futterman) is a 12-year-old human boy who was transferred from Chester Arthur Middle School to Charles Darwin Middle School (CDMS) by an accidental misspelling of his last name from "Lyon" to "Lion". As the series title suggests, in gym class, Adam was paired up with Jake Spidermonkey and the two become best friends. Jake's plans have them getting involved in situations which end up with him and Adam in trouble. Adam, being physically weak, is often preyed upon by the other animal students. His personality is downtrodden, due to being in an animal school and he also has a reputation of complaining about his daily experiences at the school. Adam can be arrogant and strong-willed at times. Outside of school, he is often seen with a human girl named Kerry, with whom he has a secret crush. His efforts to impress her end up with Adam's embarrassment. Towards the middle of the series, Adam seems to be on the borderline of sanity. Throughout the series, he has shown an extreme interest in clowns; for instance, his favorite super hero is Captain Clowny, despite the time he didn't get a Captain Clowny action figure for his birthday after making a wish on a star that he would. he eagerly hopes to attend a clown-based summer day-camp and his college of choice is Clown College, as seen on his resume in the episode "My Feral Lyon".