Associate Professor Akira Takatsuki's Inference.

Eight years ago, a boy who got lost in a festival surrounded by the suspicious light of blue lanterns. Everyone wears a mask and continues to dance silently. It was a festival that no one should ever enter—the boy meets his grandfather, who should have died there. "Naoya, you couldn't come to such a place…" Naoya Fukamachi, who became a college student, lived with loneliness. Naoya has been able to understand people's lies since the day of the Blue Lantern Festival. When a person tells a lie, his voice is distorted and sounds strange.