The moment a gorilla shows up to high school like he belongs there, you realize this show doesn't follow any rules you know. Every episode throws another absurd character into the mix, a guy who's literally a robot, a thug with his own theme music, a delinquent who just accepts all of it, and the joke is that nobody questions it. The comedy escalates by pure escalation, each impossibility treated as casually as the last, until you're laughing at the sheer defiance of it all working.
Kamiyama transfers to Cromartie High School expecting a normal education. He quickly discovers normal stopped existing the moment he walked through the gates. This is where society sends its most violent delinquents, its most incomprehensible thugs, and apparently its gorillas and robots. His classmates include a guy with a purple mohawk who communicates primarily through grunts, a student named Mechazawa who may or may not be a cyborg, and Freddie, a brutish manchild who insists on having his own personal theme music playing at all times. Nobody seems particularly interested in actual academics. Instead, Kamiyama spends his days navigating absurd confrontations, bizarre friendships, and the constant confusion of trying to figure out what the hell is actually happening around him. The comedy comes from how seriously everyone treats complete nonsense. Freddie's theme music swells during mundane moments. The gorilla participates in school activities like it's perfectly natural. Cameos from inexplicable characters appear without warning or explanation. It's anarchic, rapid-fire humor that rewards viewers who surrender to its logic and stop asking questions.