Kaede is a girl with long, light blonde hair featuring a prominent ahoge (an upright strand of hair) on top. Her eyes are a distinct purple. Nods to her musical talent are subtly integrated into her clothing: she wears silver hair clips shaped like musical notes and a purple plaid skirt patterned with a musical staff design. Her outfit consists of a crisp white dress shirt under a light pink sweater vest, dark purple knee-high socks, and brown lace-up shoes. She is also frequently seen wearing a simple white backpack. Personality Kaede is exceptionally optimistic, kind, and natural at taking charge. When thrown into the high-stakes killing game, her immediate instinct is to unite the students rather than let fear divide them. She is fiercely empathetic and has a strong sense of justice, often placing the well-being of others far ahead of her own. However, this intense desire to protect everyone can sometimes manifest as a stubborn, forceful attitude, pushing her to take extreme risks in order to secure freedom for her classmates.

Shuichi has a slender build, very pale skin, and short, dark navy-blue hair with a small ahoge sticking up. His eyes are a soft, greyish-gamboge color. His wardrobe is heavily inspired by classic detective attire mixed with a traditional school uniform. He wears a dark, pinstriped black jacket with silver buttons, matching trousers, and dark shoes. For a significant portion of the game, his most defining accessory is a black baseball cap featuring three white stripes, which he pulls down tightly over his eyes to avoid making direct eye contact with others. Personality Initially, Shuichi is incredibly soft-spoken, timid, and plagued by severe self-doubt. He feels unworthy of his "Ultimate" title, believing his past successful cases were won purely through luck. Because of this, he is anxious about revealing truths that might hurt people. However, beneath his fragile exterior lies a highly analytical mind and a deep sense of empathy. As the killing game progresses, he undergoes profound character growth, gradually learning to face his fears, ditch the protective barrier of his hat, and courageously pursue the truth—no matter how painful it may be.