Follow Your Passion: A Seamless Tumblr Journey
Mammon isn’t stupid, he’s *impulsive*. He allows his sin to override his intellect, which to be fair we see in a lot of other demons who don’t get characterized as stupid. He’s apparently good at math (if he thinks of the numbers as Grimm). He’s the second strongest brother, so he isn’t going to be a total airhead. His lack of emotional intelligence and self-control get interpreted as stupidity, which is unfair.