Mary Skelter 2 is a first-person dungeon-crawling RPG game that takes place in the living prison called The Jail. Developed by Idea Factory, this game is available on Windows and falls under the category of adventure games. In this game, players take on the roles of Blood Maidens, fairy tale-inspired characters with customizable character-specific classes. The game features turn-based battles with a blood-fueled transformation system and real-time chases by indestructible Nightmares.

The story begins with a group of humans known as "Dawn" trying to survive the horrors of The Jail. They succeed in saving Alice and a young man named Jack on one mission, but Alice goes mad and begins attacking those around her. During the chaos, Otsuu and Little Mermaid fall down a chasm with Jack on the verge of death. The game follows their journey to escape fate and find sanctuary in this mad world, led by a group of girls and the young man who transforms into a Nightmare. Mary Skelter 2 also includes a remake of Mary Skelter: Nightmares, with improvements made for an even more intense experience.