Adult PC Game: Mizu Kagami no Shizuku by DoubleSoftCream Archive

A young man arrives at an old house, located in the middle of nowhere, to figure out what exactly they wanted from him, writing such a strange letter, pulling his shirt pocket. Having reached the place and dusting himself off, he knocks on the door of a house that looks more like a castle. The door opens, and behind it.. The eldest of the two sisters. Just looking at it, it becomes clear that the disclosure of the secret of the letter must be delayed at any cost, because THIS cannot be missed.
For those who do not understand anything in Japanese, there is a second button from the top in the main menu, just press it and the steering wheel will jump into your hands - steer the process without background!