The search for is ultimately a search for accessibility. Until Rejet localizes the game (unlikely), the modding community remains the only bridge for English speakers. Just remember: patch your sigpatches, don't patch your morals, and always keep a backup of your original NAND.
Since an official English localization does not exist for the Switch version, dedicated fan groups "patch" the game files to replace original Japanese text with English translations. diabolik lovers grand edition switch nsp xci patched