胧月馆 [Moonlight Lodge]

"20 years ago, during the twelfth lunar month, a horrific murder shocked the entire nation. Everyone in the inn was brutally killed, and their bodies were turned into rigid mannequins. The only survivors of this case were five children adopted by the innkeeper’s wife, Kyoko, but due to the immense trauma, they collectively lost their memory. The case remains unsolved to this day. 20 years later, the five survivors receive an invitation from the famous novelist, Mr. Kazuya."