Banana Joe is the clown at Gumball 's school. When he cracks his jokes he thinks people are laughing with him when they are really laughing at him or not at all. He is also a CGI and stop-motion character, like some others in the show.
Banana Joe is an banana with googly eyes and a mouth made of clay. He wears and treats his "peel" like a shirt - he can remove it at will, and has several extras messily stuffed into his clothing drawer. The bottom end of his nude banana body is clefted to resemble a butt.
Being the clown, Banana Joe is always making jokes or trying to be funny, though his jokes can sometimes be hurtful, like how he teased Gumball to tears in The Gi . His jokes can also be annoying or creepy, such as in The Third . At first, Gumball and Darwin enjoyed his comedy act, but as he went on, he got creepier, causing them to leave him.
Banana Joe also has a distaste for girls. This was prevalent in The Pressure , where he established a "pals before gals" pact with the guys. He even resorted to chopping down the girls' clubhouse, all to prevent Darwin from kissing Masami . However, he may have gotten over this, since he didn't complain in The Party when everyone had to get a date to attend. Furthermore, in The End , he acts as the justice of the peace for Gumball 's wedding.
He also appears to be messy. His room is in desperate need of cleaning - his peels are sticking out of his drawer and there's junk scattered across the floor. Also, the stuff in his locker looks as though he just carelessly stuffed them in there. Like Gumball and Darwin he dosen't seem to be very bright but, he's quite smarter than Gumball and Darwin.