DESR VFF is a type of greyscale raster (bitmap) image file. Such a thing apparently existed at some point and managed to get on lists of image formats, from which a multiplicity of sites that purport to give information about file formats created pages with little more information than that it is a greyscale bitmap image file. Another multiplicity of sites that purport to give the meanings of acronyms also weighed in on it, with the same limited information. So here comes this site to create yet another virtually-information-free page on it... but at least this one doesn't have ads or dodgy downloads. Plus, it's a wiki, so if you happen to actually know something about this format, you can edit it to provide this information. Neat!
It's nothing to do with a BFF, which is a Best Friend Forever.