EVen if he's not the smartest of the bunch, i feel like Ryuji's stupidity was a bit overplayed some-no, most of the time after the kamoshida arc. and saying ryuji getting mad at morgana unprovoked? Morgana was always the worst about constantly needling him with insults about what a dummy he is, it got on my nerves a bit (i still love you morgana don't worry). Although there were times when ryuji should have calmed down and not let Morgana get to him and shouldn't have encouraged the kitty to up and leave, i'd say his dislike towards teh cat was at least a little justified, even if it cause dproblems.