Critters are creatures I drew in the margins of my notebooks just as a distraction, and then I started giving them their own mythology and traits, and now they're my go to thing to draw whenever I need something to practice.
They usually have feline and/or canine traits, and shift their appearances a little. They're made of shadows, and can dissolve into them at will. The older a critter is the more solid it is. Touching one is kind of like sticking your hand in a very inky cloud.