The show builds mystery by never letting you see the full picture until the moment it matters. Abe Seimei doesn't explain demons, he reveals them, and each case peels back another layer of what obsession actually costs a person. The real story isn't about solving mysteries in Kyoto. It's about two men learning that understanding a demon means understanding the person it came from, and that knowledge breaks something in you.
In Heian-era Kyoto, court musician Minamoto Hiromasa seeks answers about the demons plaguing the capital. His search leads him to Abe Seimei, an onmyoji whose reputation precedes him,a man who reads the invisible world with unsettling precision yet shows little interest in using his gifts. When Hiromasa needs his help investigating supernatural disturbances, Seimei reluctantly agrees, and the two begin uncovering a pattern beneath the chaos. Each demon they encounter carries the weight of someone's desperation, rage, or longing twisted into something monstrous. As they dig deeper, a figure emerges from the shadows: Ashiya Doman, another onmyoji whose presence complicates everything. The investigation becomes less about exorcism and more about understanding the human desires that birth these creatures in the first place. Seimei's aloof wisdom clashes against Hiromasa's earnest curiosity, creating tension that mirrors the supernatural forces they face. What begins as solving isolated incidents transforms into something far more complex: a mystery that questions whether demons are born or made.