Griver

This is a GF but you can never get it or use it, but you do fight it in the final battle thats why you have to name it near the end of disc two.  In Squalls mind this is the most powerfull GF in the whole world.  He also has a chain with a pendant of Griver and a ring with him and also on his gunblade case and if that isnt enouth its engraved on Squalls gunblade as well.  So you can see that Squall is preaty much obsessed by this GF.