Not much to say about this one, oddly.
I hadn't expected Mathis to ever get a book. I assumed that if he got one it would be pre-reveal (I actually - somehow- forgot about the reveal until Nova recognized Mathis as Breed). I'm not sure why I expected that, really since he spent most of the pre-reveal books with a human.
The romance and I love yous seemed a little rushed but that's understandable since this is a novella and not a novel. We never do find out that much about Nova's past, although she does tell Mathis some of the important parts. I think I like the name Nova better than her real one.
The murder mystery part of the plot has a sudden realization and sudden ending, but I didn't guess who it was. There wasn't really time, but still.