The game has implementation of an english version for its game menus and some in game dialogue sequences. Remember to use navigational hotkeys of Z and X. Z is for accepting an action, and X is going back. The settings option menu can be located in game by going into the settings menu which can be accessed by pressing the "Enter key" (center most button on your keyboard) There are two enter buttons, one for numpad and the other functions as a center enter key. Do not press the enter key on numpad because it will not bring up the menu screen. Let me verify this is correct, I am going to launch my game now to test this out. Success! Once I was in game, I pressed enter, then scrolled down to section "Others" clicked that, then you will see two options. Choose the first option to bring up the Option menu. From there, use left and right keyboard arrows to navigate to the Game tab. On that tab, you should see a category for language with adjacent arrows next to it. Clicking either arrow will change the default language for the game. There will be a warning prompt in red indicating that the "English" translation for the game will have bugs. Revert to the default if you are unsure. There is no actual full English translation for this game, not yet anyways.
Hope this helped you, please reply if you have further questions that pertain to this issue, and thanks.