Buffalo is perfectly fine with that fact that Donquixote Doflamingo destroyed eight cities and all the people living there, simply for the sake of keeping Baby 5 away from her "boyfriends".[1] He seems to be a compulsive gambler, and enjoys gambling as he asked Baby 5 for a loan of Beli2,000,000, despite just teasing asking her how high in debt she is, so he can take it to the casino after their mission.[1] He apparently does not approve of cheaters, as a group of hustlers swindling a blind man in Acacia were noted to only have been doing so because of Buffalo's absence.[3]
Despite his aloof and greedy personality, he also seems to be very enthusiastic, as he is almost always seen smiling. He also has a habit of saying "nnnniin" during his sentences, to imitate the sound of a propeller.[1]