Aa is for Apple.
Presenting (from left to right) Amnesia, Andy, Autumn, Arithmetic and Abstract.

The major point to Amnesia's identity, is that it is in perpetual crisis. Forget about trying to reassure him, he can't even remember he's not supposed to be a watermelon.

Andy may have the most "normal" name, but he is really a kaleidoscope of personalities. He is all about mixing and matching, and of course, the occassional can of soup.

Some think that Autumn is shy, and possibly lonely without his other companion seasons. But maybe he just likes the colour of his feet.

A sight problem with one of his legs makes Arithmetic look like he's about to fall backwards from a certain angle. But he's got his numbers right, and that keeps him in balance.

The cool one of the lot, Abstract is bold and brash, and has a somewhat different way of thinking from the rest. That's why he's sometimes featured upside-down.