Nightwalker: The Midnight Detective is a late night anime TV series created by Ayana Itsuki that is adapted from a PC game titled Mayonaka no Tantei Night Walker. Nightwalker incorporates elements of the horror, detective story and vampire genres, and is critically noted as a vampire story "with a bit of a twist". The main character is Shido, a vampire who protects humans from other supernatural creatures. A private investigator by day and a demon hunter by night, Shido solves murder cases caused by monsters called nightbreeds.