In Sleep You Know - Christiane Knight

Even the grittiest blue collar city has a spark of magic under the surface; but in Baltimore, graffiti holds secret messages and artists are the spellcasters. Abandoned buildings hide ancient beings, and at the local club, you might find yourself rubbing shoulders with menacing and otherworldly creatures. If you know how to look, of course. Merrick Moore is just a regular guy with dreams of making it big with his garage band, but not much else - until he crashes a party thrown by reclusive eccentrics...