Flames were swallowing the sky. The clan that once shook the world of martial arts had collapsed miserably, and blood and corpses were scattered beneath the crumbling pavilions and charred walls. In the center of it all lay a man. "The First Young Master of the Clan, Guest." His entire body was covered in gashed wounds, and crimson blood flowed incessantly. Captured by the Blood Cult, he had become a living test subject, enduring the agony of his body and mind breaking down. In that process, he was forced to accept the Blood Cult's forbidden arts, dharma power, and blood energy. And in the final moments before death... Truths he hadn't known in his past life surfaced one by one. The servants who had mocked him. The group of pavilion masters who had embezzled the family's wealth. Those who had exploited the clan's downfall. And Seol Ran, his fiancée, who had betrayed him from the closest proximity. The moment he realized all the truths, So Cheon-ho's consciousness sank into darkness. But when he opened his eyes again... It was neither the Blood Cult's laboratory nor the burning clan estate. It was the bed in his familiar room... And it was exactly ten years ago. His parents had already passed away due to a bandit raid, but this time was different. Guest retained the memories of his past life. The people who betrayed him. The ones who would destroy the clan. And even all the tragedies that were yet to unfold. However, memories alone were not enough. To protect the clan and achieve revenge, he needed overwhelming power. What Guest chose was not the martial arts of the Righteous Faction. It was the forbidden art he had been forced to learn while living as a test subject for the Blood Cult. "The Tathagata Sacred Heart Scripture." It was the ultimate technique of the Blood Cult that operated blood energy and dharma power simultaneously. In his past life, it was the power that had driven him into agony. But in this life, he chose that power for himself. Every night, unknown to anyone, he continued his training, accumulating blood energy and dharma power, and even began to absorb the vengeful spirits dwelling in antiques that ordinary martial artists wouldn't even glance at. As time passed, his power deepened. On the outside, he was still the incompetent, scoundrel First Young Master, but inside, a monster entirely different from his past life was growing. And finally... The ones who had betrayed him in his past life began to appear one by one. The first target was his fiancée, Seol Ran... The person the past So Cheon-ho had trusted the most... But the Guest of this life knew her true nature. The moment he looked at Seol Ran with cold eyes, The first chapter of revenge began. The man who was called an incompetent scoundrel. The scoundrel First Young Master of the clan who returned from death. The man who chose the Blood Cult's forbidden arts for himself. And the name that the entire Murim would come to fear in the future.

"The Blood Demon, Guest."

His second life was beginning.