People will call this story fiction, but only one man knows it is an autobiography. Once known as the "Hollow Blade," a legendary assassin whose sword determined the end of mortal stories, the protagonist lived through kingdoms becoming ruins and gods becoming myths. His life changed the moment he crossed blades with Supreme Divine General Aria, the "Sword of Dawn," and realized he was simply a man who had fallen in love with the only person trying to kill him. After throwing himself into a killing strike to shield her from a divine spell that fractured the sky, he woke in Hell—a kingdom built not from fire, but from the weight of eternal regret.

Driven by a promise to find her again, he spent seventeen centuries climbing the hierarchy of the underworld, eventually claiming the Black Throne only to trade his crown for a "borrowed life" in the year 2007. Now inhabiting the body of a man named Itanabi Nightshade, he inherits another's scars, debts, and nightmares while searching for the woman he died to save. He finds her, but the gods have been cruel: Aria’s soul has been divided into two separate women—one carrying her courage and strength, the other carrying the grief and tears she once hid from the world.
Bound by a divine condition that he can never reveal the truth without causing their human vessels to die, he must love two hearts that were once one, becoming a bridge between two lives that can never be whole while he remains beside them. As he navigates the modern underworld to protect them from shadows they cannot see, he discovers that the hardest journey isn't surviving Hell, but finding the courage to let the person you love believe that losing you was their own choice. "I'm Sorry For It All" is a record of everything he was too late to save and a testament to a sacrifice that history will never applaud.