A custom skin pack or a specialized resource pack featuring these two characters.

These are likely the names of the characters or creators associated with the file. Yumeko and Gabi are popular names in anime (e.g., Yumeko Jabami from Kakegurui and Gabi Braun from Attack on Titan ).

These are Minecraft section signs used for formatting text colors. In Minecraft's code, §4 represents Dark Red , and §f represents White . This strongly suggests the file is a Minecraft resource pack, skin set, or world save intended to display colored names in the game's menu.