Mystery of the Necronomicon

Mystery of the Necronomicon (黒の断章) is the title of an H anime created by Abogato Powers and released in 2001.

Plot
Private detective Satoshi Suzuhara and his adoptive daughter, Asuka Kashiwagi, are spending time at an isolated ski resort. But when a snowstorm cuts off all links to the outside, Satoshi becomes the main suspect as a string of gruesome murders are being done on the guests at the now cut-off resort. It becomes a race against time as Satoshi must find out who is behind the murders.