It did feel a little bit rushed lole I knew from the beginning the emperor was innocent cuz they kept giving clues but I think the author just wasnt sûre on who to keep as the actual villain I think. And came to the conclusion that it best to have the empress be the final villain. Honestly I feel bad for the emperor, dude loved the empress, the empress was just a sociopath, his dad was a psychopath and vuz of lies he ended up isolating his nephew and distrusting his brother