Pascal (spoiler)
Although Pascal ruins the brothers in the end, I think he is the funniest character in this movie. And that's saying alot, since the brothers themselves are hilarious.
Great Pascal lines:
"Sink your teeth into the ass of life and DRAG IT TO YOU!!"
"There is never too much! There is only NOT ENOUGH!!"
"I should kill you!...This is so *beep* good, I should KILL YOU!"