Ah, he goes by Luffy, actually... Straw Hat Luffy. Monkey is his surname.
If he were here, you'd know it... He's not the type to blend into the crowd. Shit... [ That means he's not here. Which is a good thing because Luffy can continue on his journey - but a bad thing because that decreases the possibility of escape. ]
What about a talking reindeer named Tony Tony Chopper? Green-haired swordsman named Roronoa Zoro? Do either of those sound familiar?