Raccoon

Tanuki are a species of character in Animal Crossing. Tanuki are frequently confused with raccoons in Western culture (and referred to as raccoons in-game). All Tanukis so far have been special characters, and worked in the same place, similar to Pelican characters.

Special Characters
Timmy and Tommy are twins, and are Tom Nook's Nephews. They only work in Nookingtons on the second floor.

Tom Nook is the main Tanuki in the game, being one of the first special characters to appear. He is the one who built the players house, and expands it, as he is the one you pay mortgage to.

Connection with Furniture/Leaves
In traditional stories, the Tanuki raccoon was said to have had the ability to transform leaves into gold. Tom Nook seems like a greedy character at first, he may possess the ability to transform leaves into bells as he seems to have an unlimited supply of it. However his ability would make him an honest merchant as he does not use it to pay for store upgrades. This would also explain why furniture is depicted as a leaf while on the ground outside, or handing it to a villager or special character. It would also explain why Nook's shop uses a leaf as a logo.