Yuna was just an ordinary forensic investigator—until the night she encountered Aspan, a cunning and enigmatic demon bound by an ancient curse. What started as a terrifying brush with the supernatural became an obsession. As Yuri delved deeper into forbidden knowledge, she found herself recruited by a top-secret FBI division specializing in demonology and occult crimes. Now, armed with her newfound expertise and an uneasy alliance with Aspan, she must navigate a world where demons walk among humans, uncover dark conspiracies, and decide how much of her own humanity she’s willing to sacrifice for the truth.