You may optionally install a mod to add in the extra content in the Denpa version if you bought the game on Steam.
1. Find Sunrider Academy install location by right clicking the game on Steam and pressing properties
2. Press “Local Files” tab > Press “Browse Local Files”
3. Open the folder called “game”
4. Download additional content (109 MB) (MIRROR) and drop the three files in the patch into “game” folder
5. Start game on Steam. Content warning should appear & “Denpa Edition” should appear at the bottom left side of the main menu