On a rainy night at a lane's entrance, a life-lamp flickers. She takes “Mu” as her name. A life-lamp master, she can mend other people's lamps, but each time she does, her own lifespan dwindles. He lives by “Mu,” a black-clad swordsman who bears his family's curse and guards the rift in the Abyssal Chasm. By chance, she glimpses the shadow of his lamp, bound by an ancient oath. From that moment on, their fates are tightly linked by a lamp and a stone inscribed with the character “Mu.”
From Abyss City to the Ruins of Return, from the power struggles of the Life-Lamp Bureau to the giant beasts beneath the Abyssal Chasm, they choose each other again and again amid storms and betrayal. When the Abyssal Lord seeks to use all living beings as fuel to restart the Abyssal Chasm, they must take the lamp as their key and their hearts as blades, rewriting their fate and redefining what it means to protect someone.
