Denji is a teenage boy with blond and scruffy hair. He has yellow-brown eyes and bags underneath, resulting in a dazed and tired expression. His teeth are noticeably sharp and angular. Denji is both brash and naïve as a result of being unable to have a formal education and socialize due to living in severe poverty. His personality comes off as rude and harsh in an almost childish way. However, he has a good sense of empathy towards other people, willing to save those in danger.