Shisha no Yobu Yakata (2000, Playstation), part 4 (final part)

According to the VNDB, the game has 28 different endings. As far as I could find out, this playthough does not have the best ending.
There are supposed to be bonus features available if you discover enough endings.

Shisha no Yobu Yakata (死者の呼ぶ館, roughly "The Mansion of the Calling of the Dead") is a visual novel developed and published by Pandora Box. It was only released in Japan.

You play a young main who has just finished university and has taken a sidejob to be the tour guide on a one-week trip to a villa in the countryside. The group consists of six rather peculiar customers. After arriving at the local station, the local contact who was supposed to bring everyone to the villa does not show up. Since the customers get more and more anxious to get to the residence, you finally decide to lead everyone to the villa yourself, using a map. However, you get lost in a forest you have to go through. The forest is called "The forest which eats people" and "The forest without return". Close before dawn, you suddenly come about an old yet beautiful mansion which lies deep within the forest. Since everyone is tired and there is barely a chance to reach your actual destination before nightfall, you ask to stay a night at the mansion. A mysterious, yet not unfriendly old man opens and readily agrees to your bidding. However, you cannot shake the feeling that there is something very odd and frightening about this place. It doesn't help that the mansion has no phone and your mobile no connection...