Four thousand years is a long time. But you've toughed your days as an angel out, and you've somehow managed to continue living in the Celestial Realm without Lucifer to brighten your days. But when Diavolo's student exchange program brings you back to the man you once knew so well, you find that things aren't the same. Because four thousand years is a long time. And the love you once felt for Lucifer has changed into something different. Something special. Something romantic. But, above all else: something forbidden.