How the Curse Works
The first sign of the curse is bad luck. The luck will get worse and worse until you can't stand it anymore. It waits until you are vulnerable. When you reach this point, it will take something away from you that means a lot. He will continue doing this, until you have barely any strength left. While he does this, he will message you from time-to-time, usually in the form of sticky notes, or writings on the wall (that are usually made of blood from a victim). Sometimes, however, this won't happen or only one will.
After a time passes, the Tails Doll will almost certainly come to you, but he is far from benign. If the Tails Doll hasn't already killed you, he will sometimes offer you a deal; pledge your soul to him and become a servant, or be forcefully taken and enslaved. Either way, there is almost no way to get out of this deal with the devil, but a crafty few have outwitted the Tails Doll. Be warned, though, as even if the Tails Doll is scammed out of a deal, victory will always come at a price; the Tails Doll will decide that.