Crazy, silly, and unrealistic moveset wise. Also a character this is not mainstream or popular and a surprise pick. I guess more like how we would describe WTF characters.
Why I say ROB and Game & Watch:
Game & Watch - He throws bacon in a frying pan at you, rings bells, hits you a large fish, etc. He was out of no where, he really was not a true video game character, he had a humor aspect with regard to his moveset and design.
ROB - Another out of no where wtf character that has a kind of humorous moveset and at first glance didn't fit in the roster (but to me he was one of my favorite additions and I think he fit well).
I guess I look at it by the intention/motivation Sakurai had for adding the character, his moveset, design, etc. I can also picture Sakurai and the designers laughing at some of the ideas for these characters.