These creatures look a dog/weasel mix, they have low-slung foreheads, black skin and hair, and glowing yellow eyes. All this is accompanied by short, stubby legs, a long boday length, a whip-like tail, and a mouthful of dinosaur teeth. Not only that, but according to Robin Goodfellow, "...they smell like dog piss."
Whatever they bite, and don't take with them, tends to rot off of its own accord. The process is very painful, and can last several days. There is no antidote for a Cadejo bite.