Taking Orders in the Underworld by Gwyneth Lesley

Welcome back to the Underworld…
Nika is not happy.
Garth’s little Rae of sunshine might have joined the team and saved them from their eternal creditor, Zeus, this time – but Garth has had enough. When he forgoes the libations agreement in favour of striking out on their own, the team at the restaurant begin to lose business … fast.
When Garth suggests Nika go trolling for customers on the cobbled streets of Asphodel Meadows, Nika comes up with another plan. If only that useless puppy-dog dryad, Tomas, would stop getting in her way.