Kamaitachi no Yoru

Tōru and his girlfriend Mari are on vacation at a skiing lodge when they find themselves suddenly drawn into a horrible murder mystery. The player must solve the crime. If they are too slow in collecting clues, additional murders will be committed, and will eventually result in a horror movie-like ending. The goal is to complete the story and get a certain number of endings. When this happens, two more stories are unlocked. Getting every possible ending of all three stories will unlock two more stories, these being self-parodies. Completing these unlocks one final feature, a parody of Torneko no Daibōken: Fushigi no Dungeon. None of the stories are related to each other in any way, but they all feature the same characters.

The gameplay mostly consists of still pictures with text covering the whole screen, which must be read. The player must make choices, including the choice of pointing out who the murderer is. Clues are often misleading, and the true clues are often well-hidden in nonsensical places, like ridiculous dialogue.