The Wizard of Ambermere (Urban Fantasy Trilogy)

Trolls? She had trolls? Was she going to be responsible for an infestation of demons? Had her apartment become a vestibule of Hell? Marcia stared at the wall behind her guest. Trolls! Or gnomes—whatever. She had never even had roaches. She looked furtively from side to side, moving only her eyes. There were no little creatures in sight. No pixies; no fairies with fluttering wings. Everything was, for the moment, perfectly normal. Just her and one not very large demon, eating doughnuts.

This is the exciting third book in the Ambermere Series