Diane — The Seven Deadly Sins

Long before the Sins reunite, a young Diane shelters the injured, amnesiac Harlequin, later known as King. They live together for about five centuries and form a deep mutual attachment. King teaches Diane to make clothes, and he once arranges her hair in the pigtails she continues to wear. When King must leave to answer for the deaths associated with Helbram, he erases Diane’s memories of their time together. Thus she meets the Fairy King again without knowing how much of their history has been taken from her.

Much later, during the battle in the royal capital, King finds Diane gravely wounded and turns on Helbram. The confrontation connects his concern for Diane with the unfinished tragedy that once separated them, even while Diane still lacks the memories needed to understand the whole connection.

As a trainee under Matrona, Diane is caught in a Holy Knight ambush designed to destroy the feared giant warrior. Matrona shields Diane from a poisoned attack and seems to die after fighting the attackers. The surviving knights falsely blame Diane for murdering Matrona out of envy and for the deaths of their comrades. Facing execution for a crime she did not commit, Diane is rescued through Meliodas’s intervention and becomes one of the Sins. Her title of Envy therefore originates in a distorted accusation, not proof she committed the alleged killings.

During the conflict with the Ten Commandments, Gowther uses Lost World against Diane after an argument over his manipulation of another person’s memories. She gradually forgets her comrades and returns toward Megadozer. Matrona, unexpectedly alive, protects her and helps her endure the dangerous journey. Even with gaps in her memory, Diane keeps acting to protect those around her; she is drawn into the Commandments’ deadly Vaizel festival while separated from most of the Sins.

Matrona teaches Diane the dance associated with Drole, the legendary giant king. When Diane and King later undergo training from Drole and Gloxinia, they experience the Holy War of 3,000 years earlier and confront choices made by their predecessors. Diane rejects the idea that a giant must surrender to the same violent fate as Drole. The trial restores her lost memories, and she develops a stronger connection to the earth through Drole’s Dance. Drole also comes to regard her as capable of succeeding him among the giants.

When Diane returns from her trial, she confronts Gowther, who would rather suppress painful memories than face them. Instead of retaliating for the harm he did to her, she urges him to recognize those experiences as part of his heart. A magical heart preserved by King Bartra also helps reconnect Gowther with his lost memories. Diane’s willingness to help him matters because she herself has suffered from having her past taken away.

Diane continues fighting beside the reunited Sins through the struggle against the Demon King. At Lake Salisbury, she builds up her strength with Drole’s Dance and unleashes Mother Creation, using an enormous upheaval of earth to separate the enemy from the magical lake that sustains his power. The maneuver changes the conditions of the battle: her power protects her friends not simply by striking harder, but by taking away an advantage their opponent had depended on.

After the confrontation with the Demon King, the group faces the final upheaval surrounding Merlin, Arthur, and the awakening of Chaos. Diane survives these events and shares in the Sins’ eventual decision to seek lives beyond the wars that first brought them together.

During the battle with the Demon King, King asks Diane to marry him, and she happily accepts. When the Sins later part ways, Diane and King look toward creating a shared home for giants and fairies. The original manga brings their relationship into its epilogue: when the Sins reunite years later and meet Tristan, the son of Meliodas and Elizabeth, King compares his cuteness with that of his and Diane’s own child. The final chapter does not name or depict that child in detail. Specific later family developments belong to the sequel, Four Knights of the Apocalypse, rather than to the original manga’s ending.