Kaede Manyuda is a student at Hyakkaou Private Academy, where he serves as the treasurer of the student council. He is a tall, pale-skinned young man with a slender build, standing at 180 centimeters. He initially has neatly styled black hair and dark eyes, and is rarely seen without his signature black-framed glasses. He wears the standard academy uniform, which consists of a red blazer with black trim, a white dress shirt, a black necktie, and dark, plaid pants.

His outward demeanor is cold, ruthless, and highly calculating. As a gambler, he is extremely prudent and observant, preferring to take what he calls the high road to victory. This mindfulness allows him to predict his opponents' actions with a high degree of accuracy. However, this calculating exterior conceals deep insecurities. He harbors a profound fear of being deemed worthless and discarded, a motivation that drives him to succeed at any cost. In this respect, he shares a fundamental similarity with fellow student council member Itsuki Sumeragi, whose tenacity he quietly appreciates.

Kaede's primary motivation is to overthrow the student council president, Kirari Momobami, and claim the position for himself, an ambition driven by his father's expectations. He is manipulative and views other students as potential pawns or stepping stones in his quest for power. He was the one who recommended Itsuki Sumeragi to the student council, though he privately looked down on her perceived lack of talent. His role in the story begins in the background, helping to orchestrate gambling events, such as the match between Yumemi Yumemite and the transfer student Yumeko Jabami.

His scheme backfires when he is publicly accused of sabotage during that event. Taking the stage to deny the allegations, he instead announces his bid for the presidency. This forces him into a public "Choice Poker" match against Yumeko, with the student council's vice president acting as the dealer. Initially, Kaede dominates the game, using his analytical skills and immense funds, which he leverages as treasurer, to gain an advantage. However, Yumeko exploits his psychological need to always win with his strongest hand. She goads him, using Itsuki as a patron, until the stakes escalate dramatically. In a critical moment, the dealer is revealed to be none other than Kirari Momobami in disguise. Pushed to his limit, Kaede is forced to bet his own life. Yumeko ultimately wins with an unexpected hand, plunging Kaede into shock and ruin. Kirari coldly fires him from the student council, and the trauma of his defeat is so severe that his hair turns completely white, a condition associated with extreme stress.

After his downfall, Kaede becomes a broken and apathetic figure. He is hospitalized and cared for by Itsuki Sumeragi, to whom Yumeko had given his life debt. He is listless and sees no meaning in his existence, often urging Itsuki to leave him be. His character begins to develop again when Yumeko recruits him to participate in the Greater Good Game. Initially indifferent, he regains some of his former sharpness, collaborating with Yumeko on a bluff and correctly deducing the true traitors in the game. When another player attacks Itsuki, Kaede instinctively moves to protect her, showing a residual concern he had not previously expressed. Itsuki also reveals that her involvement in the game was partly a gamble to restore his fighting spirit, leaving him conflicted about her feelings for him.

Kaede's key relationships are complex. He has a deep respect for Yumeko Jabami's abilities, even as he considers her an enemy and a potential pawn for his ambitions. She, in turn, sees through his calculated nature and exploits it for her own victory. His relationship with Itsuki Sumeragi evolves from one of condescension to a more nuanced bond. He initially scorns her but later develops empathy for her as they share a similar fear of failure. After his defeat, he is dependent on her care, and their dynamic takes on a new, more intimate dimension. In the spin-off manga Kakegurui (Kakkokari), his usually serious nature is occasionally contrasted with a hidden, perverted side, such as when he misinterprets a comment about Yumeko's gambling skills as something sexual. Kaede's notable ability is his strategic mind; he is an expert in financial manipulation and psychological analysis, using his position to control the flow of a game through sheer economic power. However, his predictable adherence to the "high road" and his arrogance ultimately become his greatest weaknesses.