Heizou, 16, is a free-spirited, playful, and unruly high school student. He's cheerful and lively, a bit of a wise guy. He has a wild imagination, but also very logical. He's smart, and intellectual with a strong intuition. He is witty, charming, kindhearted, loves to help people, and has strong sense of justice while also not playing by the rules. He loves mysteries and puzzles. He's friendly, although most think of him as a charlatan. He often emphasizes words and speaks with an euphonic tone.