Asha isn't dumb but he isn't cunning either. He just thinks it's impossible for him and the emperor to get married, that's why he doesn't even entertain the thought of the emperor's affection towards him as anything but platonic. He clearly is smart and he is the treasure of his family for a reason. Also if you don't like how the emperor is then stop reading because we all know him and Asha will get together in the end ( ̄へ ̄)
We are just in chapter 10 but I don't think he is dumb, he is kinda smart, he is well aware that he got demoted before because he fell asleep and ignored the emperor, so he knows he can't reject the emperor if he doesn't want problems. Also he is book smarts, he knows the marriage law text by text too, so he thinks it's impossible for anything to happen. It's more like he is chill about it and just going with the flow rn. And on top of that it doesn't seem like he has hard feelings for the emperor, it's more like he is used to him and doesn't mind his whims, he knows he is weird but he can't do anything about it and so far he accepts him as he is
Stilll clenching my ass hoping Asha isnt this dumb. Please, make him a cunning bitch or something cuz ain't no way he is THAT DUMB. And also its stupid how an emperor is acting like a groomer, eww get away from me