Most .rar files for VaM are meant to be extracted into the AddonPackages folder within your Virt-A-Mate directory.

This "Qiusi" package is a character preset. In VaM, a .rar or .var file like this typically contains:

Modern versions of VaM prefer the .var format. If the file remains a .rar , it may contain subfolders (Saves, Custom, etc.) that need to be merged with your main directory.

Custom sliders that define the character's facial structure and body shape.