Favorite Ruler?

Nobody's going to go with Caligula? After the fall of the roman empire and the death of Octavian, Rome had a string of really awful, cruel, and generally fucked-up rulers; Caligula as the worst of the lot. He had repeated sexual intercourse with his horse, and killed his own father at a young age. He then proceeded to appoint his horse as a member of the roman senate, constantly keeping it turned around as to remind the senators that they were all horses' asses.

How could you not love that? XD