Daemon

Name: Sesheta

Sex: Female

Form: Nebelung cat; though Sesheta is more saturated in color (closer to Ienzo's hair color), sports a rather nasty scar across her chest over her heart, and is polydactyl. She also tends to shimmer faintly when Ienzo uses magic.

Additional notes: Given that Ienzo has already been forcibly separated from his daemon in a sense in canon by losing his heart, then re-united with her by regaining it, I'd like to say that Ienzo has the same distance limitation as Lyra, Will, and the Witches do in His Dark Materials (ie, much further than most humans), that the forced separation and rejoining of his heart works much like the separation by going to the land of the Dead, or to dead areas.
I'd like it also if Sesheta could use / share some of Ienzo's magic. Spells he cast that affect him (like Vanish) would affect both of them; it'd be neat if Seshata could also use all of his non-damaging spells on herself (Vanish, blurr, Disguise, etc), and that as Ienzo gains in power if she could gain more powerful illusion abilities (perhaps a bit like a Cheshire cat, the ability to just make parts of her body vanish, or appear to be in different places).

Why this form: I know, I know: cat. how boring! I did consider a number of more exotic animals, including a grey crowned crane, but the cat, particularly the nebelung, fit Ienzo the best.
Nebelung cats are said to be mysterious; they are often very reserved, though they will bond with a few close individuals. They are highly intelligent animals as well. More than that, though, Ienzo prefers not getting his hands dirty. While not lazy, per se, he uses his own talents to his advantage and avoids combat, letting others do the dirty work... much as cats have latched on to humans as a way to get food, shelter, and protection. A cat is still playful at times, and a cat can still hunt its own food, but cats rely on others for their protection in the end. They are also sly and the traditional companions of both witches and writers, which Ienzo is sort of both.
The name, Sesheta, is a reference to the Egyptian goddess of both writing and science, things Ienzo is also associated with. Sesheta, like many Eyptian goddesses, is ALSO associated with cats.
Finally, we have the slight connection to the cheshire cat, a cat who can turn invisible and speaks in riddles that hold some truth. In the same way, Ienzo will often speak cryptically with clever wordplay, and he is an illusionist... though Sesheta isn't much of a smiler.