A few years after the Demon Lord's defeat, the kingdom holds a memorial service to honour the lives lost in the battle, and the Hero takes this opportunity to reunite with the princess of Ludonia, whom he first met at the beginning of his journey.

But the princess is not happy to see him; in fact, she accuses him of murdering her elder brother, the Hero of Ludonia. The Hero is quick to refute this, and that triggers a trip down memory lane—one that leads him to recall the circumstances that led to the other Hero's death.

Who Killed the Hero?, Vol. 3 weaves a story that challenges perceptions and explores the intricate web of past relationships and hidden motives.