Katsuki is a very aggressive person and bullies Izuku Midoriya, who he also treats in some ways as a rival. He has a superiority complex and wants to be first, to be the best at everything. He doesn't like when people look down on him, as if they were superior to him, and gets mad easily. He is extremely arrogant, but also very smart and capable. He also thinks of people such as Izuku Midoriya as an obstacle on his path to becoming the greatest hero. (Source: Boku no Hero Academia Wikia)

Oreki is a high-schooler with messy brown hair and green eyes. Due to his very lazy lifestyle, he almost always has a tired or bored look on his face. His hair is especially very messy when he wakes up. He is shown to be a quiet student, and never concerned about things that happen around him. Despite being shown as an average high school student, he is quite intelligent and perceptive. The reason for his usual laziness is because he wishes to "save energy." Even though he is shown to be quite lazy, he never leaves his homework undone, as pointed out by Satoshi. He's considered lazy and apathetic, always living on the "gray" side, and is not interested in any activities that might waste his time and energy. He actually never intended to join any club, but his sister ordered him to join the Classics Club to save it from being disbanded. Even though he might not seem it, he's unbelievably good at solving mysteries and seems to be able to always find a solution if he gives it a thought. He has a habit of holding his bangs whenever he's thinking about a mystery.