I wouldn’t say oblivious so much as self righteous and self centered. He has his head so far up his own tuckus that he couldn’t hear a train if it were bearing down on him.
I mean, he purposely kept Perez at a distance, refusing to even think of passing on the title of crown prince to him simply because Perez looked like the former emperor.
Yet at the same time, he refused to give the title of crown Prince to the first prince either because he wasn’t ready to even think about the day he might have to give up the throne.
Instead he just sat back playing stupid games and smiling because he thought he was the smartest person in the room and thus, the mastermind of moving people around like chess pieces.
When the truth is that he’s been being played by both sides the entire time. Basically he’s too egotistical to even realize, let alone admit, that he could possibly have made any mistakes.
Even now, he can’t pinpoint where he, himself, went wrong and is trying to blame everyone else.
The Emperor is so...oblivious. Whether it's the protagonist or antagonist they use him and he don't even know it. Like sir be more aware of the people around you lol. Even so, I'm rooting for Tia and Perez