I'm writing a thesis on the emperor in the Byzantine Empire (image, cult, concept, diplomacy, the way he was perceived, politics, court manners, actually all aspects of this institution). Can someone help with some book recommendations?
I think this title should be helpful to you: Byzantine Court Culture from 829 to 1204 by Henry McGuire. McGuire argues that the court in all its forms was constantly changing, and that these changes had an impact on contemporary art and architecture.
I also came across this article: THE EMPEROR CULT AND THE ORIGINS OF THE ICONOCLASTIC CONTROVERSY L. W. Barnard Byzantion Vol. 43 (1973), pp. 13-29. This is a great resource on contemporary perceptions of the emperor and how it was reflected in art and literature.
Look at the books cited in this answer by /u/mp96 and in the subreddit booklist, but they're probably already familiar to you.