Kanzaki Nao is a young woman of twenty years old during the events of Liar Game: The Final Stage, having first entered the deadly tournament two years prior as an eighteen-year-old college freshman. Her most defining characteristic is an almost absolute honesty that earns her the nickname foolishly honest from those around her. This trait is so pronounced that she would famously report a lost one hundred yen coin to the police, a detail that illustrates her fundamental inability to deceive or be disingenuous. Despite being frequently deceived throughout her life, she maintains a cheerful and energetic disposition, though her constant exposure to betrayal often leaves her in tears.

Nao's role in Liar Game: The Final Stage is that of the story's moral center and a player who has become more resilient through her traumatic experiences in the tournament. While she enters the game due to her honest nature, she remains in it by choice, driven by a powerful altruistic motivation to save all the other participants from debt and to dismantle the corrupt organization behind the Liar Game. Her ultimate goal is to achieve an ending where everyone can walk away without financial ruin, a stark contrast to the game's design which encourages merciless competition. By this stage in the tournament, she is no longer the helpless victim she once was; having progressed through multiple rounds and a revival match, she has developed a stronger will and a capacity to calmly command and organize panicked players.

Her character is fundamentally defined by her relationship with Shinichi Akiyama, a genius former con artist whose skills complement her own. Akiyama is initially dismissive of Nao, tricking her into waiting for him for an entire day, only to be moved by her unwavering faith and reminded of his own mother, leading him to become her protector and strategist. Their dynamic is central to the narrative; Akiyama provides the logical, manipulative expertise to win the games, while Nao provides the empathetic insight to understand and unite the other players. She also has a significant adversarial relationship with Norihiko Yokoya, the primary antagonist whose company was responsible for the death of Akiyama's mother. Nao's persistent forgiveness, even towards an enemy like Yokoya, becomes a powerful tool that challenges the cynical foundations of the Liar Game.

Though her acting ability is officially rated very low due to her inability to lie naturally, Nao demonstrates significant development over the course of the series, particularly by the time of the final stage. She learns to channel her inherent empathy not as a weakness but as a strategic asset, allowing her to accurately assess the personalities and motivations of others to a degree that sometimes surpasses even Akiyama. She gradually progresses from a passive character who is constantly saved to an active participant capable of executing bluffs and even devising her own strategies based on the principle of absolute cooperation. Her notable abilities lie not in mathematical genius but in emotional intelligence and an unshakeable moral conviction. Her empathetic nature and persistent belief in the goodness of people often have a transformative effect on the other players, making her a rare figure of trust in a game built on lies, and her capacity to influence others by appealing to their better nature is a key component of her team's success.