I've been doing a bit of researched I found some similarities of Shadow and the Final Fantasy character "Vincent Valentine".

Both characters have a similar history (lost an old girlfriend, created by an evil scientist) and similar color scheme and equipment (red and black, guns and other weapons), and their association with the military (G.U.N. and W.R.O. for Shadow and Vincent respectively). So does that make Shadow (since Sonic adventure 2 was released after FF7 from which Vincent appeared) a furry version of Vincent? what do you think?

Side blog: Sonic RPG part-2

Sonic RPG part-2