Villainess Level 99: I May Be the Hidden Boss but I’m Not the Demon Lord is a Japanese light novel series written by Satori Tanabata with illustrations by Tea. Reincarnated as Yumiella Dolkness—the secret final boss of the otome game Light Magic and the Hero—a pragmatic college student hones her dark magic in solitude until she reaches Level 99, only to find herself thrust into royal intrigue at the magic academy; as princes, nobles, and even the would-be Demon Lord underestimate her, Yumiella must balance her desire for a quiet life with the demands of friendship, love, and unexpected heroism, turning the villainess trope on its head in this witty isekai saga.