Go to the Enchanted Kingdom and go to the Museum of Living Portraits.

Go to the very end and you'll find a mirror. Click on the Water Temple on the left and press play.

Get a score of at least 50,000 on it and then once you've done that, go to the Wotnot Book, click R on the page with the elemental warriors.

Then click on something called bonuses on the left page

Then there should be Kameo's Gothic skin.