Lucifer is, as his name may indicate, the devil. Ruling over 4591's Hell ever since the fall, he's now on quite good terms with Asa and helps him whenever possible, at one point being given the role of God and returning it willingly when he was no longer needed. Over time, he turned the formless pit of 'eternal' damnation into a highly structured mechanism that serves his own needs and supplies him with whatever he desires.
More later. Lazy.