Konohana 3 ~Itsuwari no Kage no Mukou ni~

The story picks up lightly with Meguru and Miako bickering about. After some computer chatting, Miako arranged to go with Meguru and Shinobu to a Water Island amusement park. There, they would also meet up with some other friends and acquaintances. Time went by as they were checking all kinds of interesting places at the amusement park, until they entered the house of horror attraction. One of the people among them was found killed in a haunted house and everyone's a suspect. It is up to Meguru and Miako to once again put their minds to the task of solving the murder mystery and finding the culprit.

[from MobyGames]