Henry Stafford, Earl of Buckingham, serves as a politically ambitious Yorkist nobleman. He emerges as a pivotal early ally to Richard III, motivated by the goal of securing the English throne for Richard. Buckingham demonstrates strategic cunning and a capacity for deception, notably disguising himself as Richard to slay Warwick in a decisive battle.

His alliance with Richard forms a central narrative dynamic. Suspecting Richard conceals a secret, Buckingham engineers situations to expose the truth, ultimately uncovering Richard's intersex biology. Privately labeling this a "demon’s body," Buckingham reframes their bond as a pact between "demons committing sin," exploiting Richard's vulnerability and desire for acceptance to augment his own political power. This complex, toxic relationship culminates in a non-consensual encounter where Buckingham rapes Richard. Symbolized by bloodied rose petals, the act is depicted as sealing a dark contract. Buckingham subsequently grows possessive, asserting dominance through public displays of physical intimacy aimed at Richard, deliberately provoking Richard's loyal servant, Catesby.

Buckingham's ambition intertwines with obsession. He perceives Richard's son, Edward, as an impediment to his control and contemplates his removal. He imprisons Richard, forcing him into women’s clothing to reinforce dominance and prevent Richard from prioritizing kingship over their relationship. Despite this manipulation, Buckingham's motivations encompass a genuine, albeit distorted, love rooted in their childhood meeting. His eventual release of Richard, enabling the pursuit of the crown, marks a pivotal acknowledgment of Richard's autonomy, preceding Buckingham's canonical betrayal.

Historically, Buckingham's trajectory concludes in rebellion against Richard, though the adaptation nuances this through personal devotion intertwined with political calculation. A confirmed detail states he fathered no children with his wife.