You'll need a software to mount the .mdf file, if you don't have one try [Daemon tools](https://www.daemon-tools.cc/products/dtLite) *Installation* >You can start playing by copying the entire ひとなつの folder from .mdf file to your desired folder. If you choose this method your save data will be stored in Documents directory. >Or you can also use the installer which provides more options than manual install. *Patch* > Patch the game to fix some minor CG issues, if you installed via the installer then patcher will automatically detect the game's location, otherwise specify where the game is located. You don't need this patch to play the game but it fixes some stuff so you might as well should use it. Have fun