Welcome.The strip is a really simple idea. Mice want to eat the cheese; the cat has cheese; the cat wants to eat the mice. Nice and simple with easy motivation to understand. Here are the characters:
The cat. The cat's motivation never changes; he want mouse for dinner. While he is not the main character, he is the force of nature that the mice must always deal with to get what they want.
The mice. The mice are always plotting to get the cheese from the cat. They are always nameless. Sometimes it is just one; sometimes a group. Sometimes they work together, sometimes they betray each other for the cheese. Sometimes they get the cheese; often they fail— and failure means the cat has mouse dinner.
The cheese. And the last character is the cheese. It is the "McGuffin" of the strip — the reason for all the conflict. The cat has it and the mice want it. It is the stuff that mouse dreams are made of.