ShotaConQuest ~They're After My Dick!~

Majority of the Japanese PC games & indie games are region locked & will cus a game breaking bugs & glitches on a non Japanese local PCs.
ether
A-hit Start>control panel>region setting, change both your format & local to Japanese (you can change it back any-time you want).
or
B-install Locale Emulator , using Locale Emulate, right-button-mouse click on Game.exe and select Locale Emulator>Run in Japanese
[keep in mind, not all Japanese games will work with this emulator method, since most of the time the game engine itself is written in Japanese & the emulator will not be able to read it from the game.exe].
Extract & play.
For more in depth guide: Some games will require an installation, as such, you should ensure your system is properly set to Japanese system locale for non-Unicode programs before starting. See Below.
Most Japanese games will require a fan-made translation patch to be applied on top of a clean install of the game in it's original language. Make sure you have both the game data discs and the most up to date translation patch from the translator's website.
Acquire and install optical drive emulation software, such as Daemontools Lite, MagicISO, or VirtualCloneDrive. What this software does is create a virtual CD/DVD drive with which to "mount" and run disc images (1:1 copies of the original game disc converted into a large data file). Typically these files have extensions such as .iso, .bin, .ccd, .img, .mdf, and so on.
Set your system to properly display in Japanese for non-Unicode programs. This ensures that the game works properly in the environment it was coded for, otherwise you may run into any particular game not working properly, such as installation failures, the game engine failing to run, garbled text, and so on.
After mounting, seek out any read-me files included with the game and/or patch for installation instructions. Most often the patch will require you to run an application after installing the game or to copy the patch files into the installation directory. If the translation group allows it, there may be an option to use the translation patch itself to install the game for you (provided you have all the necessary disc images containing the game data mounted of course).
Note: Some game downloads come pre-patched and won't require further installation. In Windows Vista,7+, it is recommended to install games outside of the default Program Files (x86) folder, due to legacy issues with how these modern OS handle the Programs Files folders and how older games modify files within those folders.