Mister Barrel

Mr. Barrel has pale skin and long white hair tied in a ponytail, with two diamond-shaped horns sticking out, which, in other words, could be his bat ears. He wears a hat with a paper school symbol on the front and the inscription "Best SG" on the back. His left eye is cursed and constantly bleeds for unknown reasons, so he covers his left eye with a small monitor to stop the blood flowing out. The monitor serves various purposes, such as displaying emojis to represent his emotions or helping with aiming to eliminate intruders. He has size-adjustable bat wings, a pair of black spikes, and a tail attached to his back.

His left forearm can take the form of several types of weapons. He has a white shirt fitted with a black tie in the middle and a red tie clip. He wears a black jacket that hangs from his waist. He wears a black bracelet on his right hand with a red circle on which the letter S is depicted. His outfit is completed with black trousers and black shoes.
Zip:Zip has short hair, divided in half into black and white. The example "2 + 2 = 8" is written on her head in blue. Various drawings are painted on the upper part of her torso: a blue smiling face, a blue house and a mahogany tree.

Her arms and legs are black, with four sharp claws instead of fingers. Zip's tail is long and spiky, similar to the tail of a dinosaur or alligator. She wears black knee-high boots with heels.