Users download a .apk file (not from the Google Play Store) that overwrites the official Dramabox. Inside the code, the developer has:
to unlock episodes beyond the initial free ones. The "Keycode-vip REPACK" is a third-party modification (often called a "Mod APK") that claims to bypass these paywalls. Reported "Features" of the Repack Based on common digital "repacks" and promotional claims in this category: Unlimited Coins Keycode-vip Dramabox REPACK