What's wrong with you?!
Well I just feel like he's become more and more idiotic as the series has progressed, from sensible if sometimes prone to a witty quip or two, as we saw in the pilot, to a point almost surpassing mental handicapation. They're just trying too hard.
And, to be honest, Cosmo's high-pitched yammering is most of what made me stop watching the show.
How did he breed?