Ripper and Hopper are the personal bodyguards of Geese Howard, alongside Billy Kane. They are in charge of Geese's protection when out of the Geese Tower. Hopper also supplied Hwa Jai with alcohol and Billy with extra staves during their matches in the original Legend of the Hungry Wolf. Ripper was still working for Geese as late as KoF '96, but his fate after that is unknown.
As a side note, Ripper likes to collect knives while Hopper collects guns. They seem to have some degree of martial art skill, but they are the men beaten by Yamazaki during the Legend of the Hungry Wolf: Distant Battle opening.