Well, DUH! Who plays RPG's? Got the answer? Now, how many people out of those like pokemon? Get that, now divide by 2. Those are how many people will like it for more than a day. Now divide by 4, (round down) got the answer? Those are how many people will like it for more than 2 days. Divide by 2, people who will like it for 3 days, now divide by 5, those are the amount of people who are going to like it for a week tops.
And, also, get this. First, take the amount of people that play RPG's, now, subtract 6, okay? Now, what did you get? Those are the people who really hate this RPG. Now subtract 14. Those people will end up going to every RPG store in the world and burn all the Instruction manuals and templates.