Tails Doll is a fictional character from the Sega Saturn game "Sonic R." It is a distorted, demonic-looking version of Tails the fox, and some people believe it is cursed because of its creepy appearance.
However, this is all just internet folklore and there is no evidence to support the existence of any curse associated with Tails Doll.
It's important to remember that fictional characters and stories are not real, and there's no need to be concerned about any potential curses associated with them.