Mixes of Optimus Prime with Rouge the Bat and Miku Hatsune with a Thanator. There are quite a few more potential slots.
A: Optimus Prime (Transformers)
B: Miku Hatsune (Vocaloid)
C: Krystal (Starfox)
D: Rouge the Bat (Sonic X)
E: Thanator (Avatar)
F: Bulbasaur (Pokemon)
I don't have a name for these combinations yet as they are just example characters.