Tails

Miles "Tails" Prower, often just called Tails, is Sonic's best friend. He is a young fox who has two, HUGE tails, which gives him his name, and the ability to fly. When he was first created, Tails was a girl. But the creators did not want viewers to think that Tails was Sonic's girlfriend, so they changed him into a boy.Soon after, they created Amy Rose.