The Secret History by Procopius

Theodora too unceasingly hardened her heart in the practice of inhumanity. What she did, was never to please or obey anyone else; what she willed, she performed of her own accord and with all her might: and no one dared to intercede for any who fell in her way. For neither length of time, fullness of punishment, artifice of prayer, nor threat of death, whose vengeance sent by Heaven is feared by all mankind, could persuade her to abate her wrath. Indeed, no one ever saw Theodora reconciled to anyone who had offended her, either while he lived or after he had departed this earth. Instead, the son of the dead would inherit the enmity of the Empress, together with the rest of his father's estate: and he in turn bequeathed it to the third generation. For her spirit was over ready to be kindled to the destruction of men, while cure for her fever there was none.

To her body she gave greater care than was necessary, if less than she thought desirable. For early she entered the bath and late she left it; and having bathed, went to breakfast. After breakfast she rested. At dinner and supper she partook of every kind of food and drink; and many hours she devoted to sleep, by day till nightfall, by night till the rising sun. Though she wasted her hours thus intemperately, what time of the day remained she deemed ample for managing the Roman Empire.