>>9521831Frame Arms Girls are all based on existing "Frame Arms" robot kits. It's kind of like those Gundam Girl drawings from the 90s, you know? Like 'imagine if Nu Gundam was gril' and all that. Pictured is the Frame Arms Greifen, and corresponding Greifen girl.
Megami Device has the better engineered body of the two lines. It's more akin to the feel of old Busou Shinki, and I think it was even designed by Masaki Apsy again. This line basically feels very similar to BS, switches designers often and the themes are sorta all over the place.