What it does:

Changes the Malkavian female's second armor ("armor1"... cowgirl) textures.

To install:

Copy the "materials" folder from this archive into the "Vampire" folder of your installation directory. 
Yours will vary depending upon where you installed the game. Example destination folder:

C:\Program Files (x86)\Steam\steamapps\common\Vampire The Masquerade - Bloodlines\Vampire