The Ultimate Yakuza. Fuyuhiko is initially incredibly stand-offish and rude to the other students on the island. When Fuyuhiko does interact with the others (by choice or otherwise), his attitude is combative and irritable. He's easily angered, often threatening and/or insulting other people when they disagree with or complain about his actions. He frequently uses the word boke (a particularly pejorative way of calling someone an idiot, often translated as all sorts of profanity), and will punctuate his statements in an argument with it. He avoids any proper relationships and he's used to being treated with caution by everyone; even to the point of threatening to murder someone.