Peter the cat is a very troubled 12-year-old tabby cat. Ever since he was a little kitten, he has been different from everyone else. Being ridiculed and tormented by all of the other kids at school has become an every-day thing for him. It is because of these problems that his Guardian, Seth the duck, has appeared. It is Seth’s responsibility to see to it that Peter survives his childhood and learns a few things along the way.

Iggy the gecko is a simpleminded little child, roughly the same age as Peter. He is an outcast from the rest of the main crowds at school, just like Peter… the only difference is that he doesn’t really care. Not being a particularly bright kid, Iggy’s ignorant nature has caused him to walk down some pretty rough paths during his childhood. This has prompted the appearance of his Guardian, Skin the snake.

Skin, a quirky little Guardian who speaks with a lisp, puts all of his efforts into keeping Iggy out of harm’s way and attempting to turn him in the right directions… but there’s only so much you can do when you don’t have any arms or hands to keep a hold on things.

Chelsea the bear is a young orphan girl who lives with her adopted mother across the street from Peter. Coming from an extremely rough childhood, Chelsea’s needs for a Guardian stem much deeper than any of the other children. However, because of her aggressive nature, revealing the Guardians’ existence to her is not the wisest of actions.

Thusly, Persephoni the bunny was called in to be Chelsea’s Guardian. Persephoni is a member of the “Guardian Elite,” and as such has the ability to transform between her true self and a small animal. In her true form she is the same as Seth and Skin, while in the latter she is seen as a small bunny and is visible to anyone, posing as Chelsea’s pet to keep a close eye on things.

Jeff the monkey is a disgruntled postal worker. He makes his runs each day to the citizens of Newington Forest, bringing them their mail and packages and such. He is accompanied by Eddy, a large blue dog who tags along with him during his route despite the monkey’s protests. Eddy speaks just like any other character, even though he is an ordinary dog. His intensely optimistic and cheerful attitude is a stark contrast to Jeff’s ultimate pessimism.

To make matters worse, Eddy enjoys nothing more than making Jeff look like a fool during his runs. Since ordinary dogs aren’t meant to talk, no one believes Jeff when he tells them about the big blue mutt’s ability to speak (and Eddy makes sure to stay silent when other people are around). As for why Eddy insists on tagging along with him… well… that’s something even Jeff would like to know for himself.

The Worms are a strange group of characters. Not quite Guardians, but not truly real either, they exist for the sole purpose of causing mischief and mayhem around the world. The same rules that apply to the Guardians concerning visibility apply to them, and they just love using the stealth to their advantage. Occasionally they’ve been known to help out a Guardian or two if they are needed, but most of the time they’re just hanging around, scheming and playing pranks on people.