"...I really wouldn't recommend it. Dealing with wish demons is a dangerous business. Their power is usually limited to carrying out wishes made by mortals, often ones who have no idea there is a wish demon present, and only within a specific domain - vengeance demons are the kind I'm most familiar with. But that would still mean that if you annoyed a vengeance demon, she could erase you from ever having existed the next time someone made a wish of which that was a plausible side effect."