This terminology is almost exclusively used in the modding and "adult game" (eroge) communities. It typically refers to a patch or a specific version of a visual novel where the "Gallery" (a section to re-watch scenes and view CG art) has been bug-fixed or pre-unlocked. Potential Contexts

Recently, there have been efforts to fix or update the gallery associated with "Futaisekai." This could involve correcting errors, improving image quality, or ensuring that the content is properly categorized and accessible. For fans of the series, having a fixed gallery means better access to the artwork they enjoy.

With the gallery fixed, you might notice empty slots you didn't realize existed. These often belong to the "Phantom Routes"—secret endings that were nearly impossible to track before because the gallery didn't signal their existence. This is your chance to scour the multiverse for hidden lore.