The prior emperor was a very...damaged man. I'd go so far as to say he's an example of how abuse creates abusers. He was a low ranking consorts child in the original imperial harem and that created an unfortunate circumstance, because he had Jinshi's level of beauty. Suffice to say he was "abused" by higher ranking concubines, and that's not really...elaborated on only that it happened. However, given how Maomao frequently comments on how Jinshi probably gets a lot of unwanted "attention", which it's revealed in more than one instance that he does, you can assume a lot with how these grown women treated a young boy who was firmly beneath them in rank. Hell, the way he reacts to being touched says a lot. Add in that he was essentially cooped up, for protection, in his mothers room, he was also clearly an agoraphobe with next to zero positive socialization from anyone other than mommy dearest. That would be all well and dandy if he hadn't been placed on the throne, but a plague wiped out the imperial family so suddenly the most powerful man in the empire is also one of the least qualified with an obligation to reproduce. The man is a product of his environment, and his crimes are likewise. Worth noting, the Empress Regnant, his mother, can be described the same way. Much of her actions, her fears, and paranoias that were played on by political "allies" can be derived from that same atmosphere and the fact that her son's position was hanging by a thread. This isn't Wu Zetian, who navigated her way to the top through guile and cunning, but rather someone who suddenly had the position of "Mother of the Nation" dropped into her lap with a son who got panic attacks from going outside.