Ciel and Sebastian returned to their mansion. In order to maintain Ciel's life, Sebastian took him back to the past, but chaos appeared in Ciel's life... One of them couldn't believe that he had fallen in love with the devil, and the other didn't believe that he had feelings; They love each other, but they do things to hurt each other in order to protect each other; they are devils, and that is why they can love fearlessly and happily; their love is firm and honest, and once they fall in love, they can never be separated... The story begins on the first day they return to Phantomhive Mansion.