Many years have past since Nightmare Moon was defeated and Princess Luna returned to normal. Some things have gone back to normal, and others have changed in a surprising way. Despite Nightmare Moon not being controlling Luna's body, she is still there, deep inside her. But this time, she's not interested in taking over Equestria, just Luna's body. But she doesn't want her body so she can walk about Equestria freely, she wants it to carry out the desires that have been building up inside her. Despite Luna's strong resistance, her will is close to breaking. How long will she be able to resist?