The Zaregoto Series is a Japanese light novel series written by Nisio Isin and illustrated by Take. It follows the protagonist, known simply as 'I', who often finds himself entangled in bizarre and mysterious murder cases, each featuring eccentric characters and mind-bending puzzles. The series is known for its complex narratives and unique character interactions, with 'Kubikiri Cycle' being its first volume and only anime adaptation to date.