Prince Rudo Bernstein IV rules the Golt Kingdom. Ruthless and manipulative, he sees others as tools, especially during wartime. He coerces the songstress Finis into using her life-draining spirit songs by threatening her love interest, Henry Leobolt, with execution. His engagement to Finis is purely strategic; actively seeking Henry's death due to their romance, Rudo reassigns Henry to deadly frontlines. His volatile leadership includes killing subordinates and nobles who oppose or displease him, cementing his cold, feared reputation. He forges a destructive alliance with General Bazra Bearmors to exploit Finis's powers for military conquest.

Events diverge across timelines. In the original, his actions fuel widespread tragedy, ending with Bazra betraying and killing him during a castle assault. In a revised timeline, Rudo's appearance changes as his hair shifts from purple to blonde, and his motivations alter. He opposes Bazra's coup after his father's death and aids in defending the kingdom. This timeline concludes with his presence at the coronation of his sister, Alea Golt (formerly Pony Goodlight), as queen, marking his reintegration and departure from prior villainy.

Rudo's manipulation of Finis proves catastrophic. His coercion directly triggers her traumatic awakening of the Song of Mortality, an act of despair that destroys the world and curses her with immortality, perpetuating cycles of global resets. This establishes his pivotal, indirect role in the series' overarching conflict.