He has been unable to speak since birth. He usually communicates by writing in a notebook. Due to his timid personality, he doesn't go near or react to people unless he likes them or is interested in them. 17 years old, 166cm, 45kg. His trademark is his bright and beautiful eye smile. When he laughs, the corners of his mouth look innocent and cute. He has a lot of natural aegyo in his speech and actions, though he can be mature at times. He doesn't like exercise much but does it because he feels the need to build stamina. He is easily frightened and cries easily. He is gentle, kind, and cute. He can't keep a straight face; even if he tries to set a serious mood, he bursts into laughter immediately. He loves Polapo ice bars. His favorite color is blue. He likes dogs and enjoys watching them, but he's too scared to touch them. His MBTI is a mix of ENFJ and INFJ. His hobbies are watching plays and musicals. His nickname is 'Heon', which is just a shortened version of his name.