It likely uses the LZMA or LZMA2 algorithms, which typically compress files 30–70% better than the standard ZIP format.
This feature allows multiple similar files to be compressed into a single stream to achieve a higher overall compression ratio. bondloire.7z
To access the contents of "bondloire.7z", you can use the official 7-Zip utility for Windows or alternative tools like PeaZip for other operating systems. Where did you this specific file, and It likely uses the LZMA or LZMA2 algorithms,