It's a bit of a problem that I didn't read the novel. But, anyway, judging from the sketches - the composition of the second one seems nice enough. I don't know about the first one, though - I don't know what it means to depict. If the guy is the mummy the mummy is - well, silent, unresponsive, inexpressive. Not much personality there - but then again, I don't know whether mummies usually have a lot of personality. What if this mummy would usually feel a bit sarcastic about things, always raising one eyebrow, sometimes smiling faintly? I get the idea that Mamabliss doesn't really know what to do with him.
A thing about colors: Egyptians probably had a dark skin tone (they do in their paintings). Certain priests, however, were used to peel their skins on a daily basis, which made them look pink all the time. A brown girl and a pink mummy would look interesting, I think. At any rate, it would draw the eye to the mummy, something which doesn't seem to happen now he doesn't have a lot of personality. Or seems rather taciturn, or whatever it is.
The girl's hair style isn't very Egyptian, anyway... Did you consider the possibility of completely shaving her? Women did shave their heads in those ancient days, you know...
