Tails the Fox

Tails the Fox
Tails is an anthropomorphic eight-year-old fox cub born exclusively with two twin-tails, hence his nickname. Because of his abnormality, Tails was the subject of bullying during his youth. Until he met Sonic, and soon became his sidekick.

In the RBJ Universe
In the RainbowBowserJunior Universe, Tails is the brains of The Main Four and is extremely smart. Going around solving problems, he most of the time hangs out with Bowser Junior. Although, he gets a bit jealous when he sees Lemmy and Cream together.

Trivia

 * It's hinted in the episodes he's in that he has a little crush on Cream.