Kuu no Mori ~Tsuioku no Sumu Yakata~

On a rainy day, Yukimura Takashi is out on a drive through a remote forest when he hears a pained voice call out his name, begging for help. Startled, he accidentally swerves off the road and wrecks his car. Seeking shelter and help, he stumbles across a rather old-styled mansion in the middle of the forest. He is welcomed inside by the butler, Kishiwada, and meets the young master of the mansion, Yuuri, who rudely tells him to get out and refuses to speak with him. There are several other inhabitants of the mansion as well, who all seem friendly or at least tolerable, but Takashi is soon plagued by haunting dreams and visions of a fire and murder, and becomes caught in a tangled mystery of the mansion....

[From Boys' Love Games Headquarters]