In the web novel 'I Became a War Hero Executed Due to False Accusations' by an unknown Korean author, the protagonist faces a tragic fate after being falsely accused by his female companions, leading to his execution. The story unfolds as he navigates a world filled with action, drama, fantasy, harem elements, romance, school life, and supernatural occurrences. With themes of betrayal, cruelty, and power struggles, the novel delves into the consequences of defeating the Demon King amidst a backdrop of fantasy creatures and a realm of sword and magic.