Where are we?

Wendy, erza, Lucy and Yukino get transported to the celestial world, there they train, learn new magic and learn they're the heirs of the four main realms, dragons, angels, elves and fairies. But when they return to earth land, nothing is there, can they save their friends and handle their kingdoms. Will they do it or will the world go up in flames?

COMPLETED
I'm sorry I wrote this years ago. It's really bad.