Ryuji is known as a disruptive "problem student" at school whose bad behavior causes all sorts of trouble for the teachers. He is quite proud of his status as a self-proclaimed "troublemaker" and his rebellious, mischievous and disobedient nature are the perfect qualities to be a Phantom Thief. He can sometimes be vulgar and aggressive, as shown in his early interactions with Yusuke Kitagawa and Makoto Niijima. He is also rather short-tempered, easily taking offense from even the slightest of comments. That said, he will never resort to violence, unless he is provoked legitimately. He is very straightforward when it comes to expressing his feelings, especially in regards to his hatred of selfish adults and authority figures who abuse their power.