Kaimetsuou to 12-nin no Hoshi no Miko

Yamikadou Meijirou appears to be an unremarkable high school student, but his life takes a dramatic turn after he rescues a demon. This encounter reveals a hidden truth about his existence: he was born bearing the Seal of Solomon on his tongue. This ancient mark grants him the extraordinary ability to command all forms of sorcery and exert absolute control over demons. However, this immense power comes with a devastating price. Every time Meijirou channels his abilities, it steadily drains his remaining lifespan, leaving him with only three years to live. Faced with this grim fate, Meijirou learns that a single path to survival remains. He must forge binding contracts with twelve mystical figures known as the Starlight Maidens. Each of these young women carries a unique celestial birthmark somewhere on her body. To successfully establish a contract and halt his impending death, Meijirou must physically touch each maiden's mark using the very tongue that bears his own seal. Thrust into a desperate race against time, the ordinary boy must navigate a perilous world of magic and demons to find the twelve maidens before his borrowed time finally runs out.