It says in Nova's Database entry that it bears a resemblance to Aisha Gauche, Soma's deceased mother. Now consider that the experiment that resulted in Soma's birth and his mother's death happened around the time that Johannes started the Aegis Project, and that it was stated that she died in a devouring accident. It's not a far stretch to imagine that whatever she was turned into became the basis for Johannes' artificial Nova...
You may notice whilst playing that a lot of Aragami have human features, especially as they get bigger; from the general humanoid shape to faces, even extending to Gag Boobs. One would think this strange, but for two facts; Oracle Cells eat anything they don't have a Bias against, and that it's been 20 years since the start of the apocalypse. A lot of humans have been eaten in that time; how likely is it that some of their traits got integrated into Aragami structure?
This also works when you consider that the bigger/stronger an Aragami is, the more likely it seems to have recognisably human features (because it's likely to have eaten more humans/Aragami). Dyaus Pita and Prithivi Mata, two hugely powerful Aragami, have human faces. Shio and the Arda Nova, the Singularity and the final boss respectively, are near-indistinguishable from human.
The name Julius is the masculine form of Juliet. Blood has both Romeo and Julius, so anyone who has read Shakespeare's work might have forseen Romeo's and Julius' ( supposed, as of Rage Burst ) death coming quite early on.
While playing you'll notice the characters mentioning being hungry a lot, and looking forward to dinner after missions. Why would they be so fixated on how hungry they are? It's the Oracle Cells within them and their God Arc influencing their behaviour; being Aragami in origin, they make their wielder/host focus subconsciously on eating.
This is even more apparent when the arm bracelet of a God Eater is broken.