While in self-exile due to the downfall of his kingdom centuries ago. His surrogate father, Sirzechs Lucifer, then summons Sirius. Fully aware of the challenges up ahead, Prince Sirius prepares for what's to come and the burdens of being a Caelum. "For we are born of the sun, made warriors by the sun, undone by the sun."- House Caelum.(Slight AU, OC no Harem)