The book is up on Amazon ==> Niko and the Shades
Niko can see the scarpies, sinister little shadow creatures who live in darkness and feed on black magic. Most people can see one or two, here or there, but Niko sees them everywhere, scuttling along the streets, hiding in shadows.
No one takes the scarpies seriously. Niko’s cousin calls them “spectral rats.” But when a powerful figure at the royal court is murdered by black sorcery, Niko begins to think the scarpies are connected. While court factions scheme for power, Niko may be the only one who can stop a magical assassin before someone else is murdered, and a killer takes control of the kingdom.