Where the hell did you see this from?!? Satan is not an Old One last time I checked and whomever thought this up certainly did not know his stuff. The person in question may have thought it an interesting idea but I see it as nothing more then some Christian writer wanting a piece of H.P. Lovecraft's pie or to force their personal beliefs into the mythos and expecting everyone to accept it. However if Satan was an Old One he'd have no choice but to answer to the lord and master of all the Old Ones; Cthulhu. Cthulhu is the only one that can summon the others to Earth or awaken them from their eternal sleep and begin the slaughter and slavery of human kind.
Yeah... last i checked, Satan is at the most basic level, an angel. So... if he were an old one, that would make Angels old ones, and God something similar.. Which.. doesn't quite seem right... Although to be fair, God is usually considered to either have no true form, or have a form incomprehensible by the Human mind. Although AGAIN, it's said he created Humanity in his image, sooo...
Actually, looking up a bit, Seraphs also, in the one instance the term is used in the Hebrew Bible, describes them as having 6 wings, two of which cover it's face, 2 of which cover its feet, and the other two for flying. Also, they seem to have depictions as being like, all wings sometimes, with no other discernible body aside from a head and what, a torso?