Coming to in a castle in the clouds, a young singer finds himself surrounded by perfect beauty as his fellow Angels are led under the rules of the mighty Sephim. With Guardians thwarting his moves at every turn the man disguises himself as a mute named Grayson and searches desperately for a way out. He soon illustrates his determination through investigation, manipulation and even arson, until the entire place is threatened to erupt in violence. With the mysterious Avis, disgruntled Tristan, meddling Fufan and a host of other characters, Grayson faces off against the woman who brought him here - Madame Lucienne - and as he learns the horrific truth he is faced with a terrifying question that will determine the fate of far more than he could've imagined. Like the bird in the golden cage adorning his room, Grayson is a prisoner of paradise.