Future's Promised

If you will be given a chance to wish for something. What will it be? It can be Power, Money, or Someone. Me? I will wish for a gate or a portal to the past. Why? I don't really know. I just want to change history. I just want to be happy! Can you blame me for being selfish? Then you must know first what I want to change. The reason why I choose to change it. This story will tell you what will happen if I will change the past.