Death by Chocolate — Michelle L. Levigne

Fae use dark chocolate as a cure-all, so how did the Queen die of eating too much?
Epsi gave her former school chum a boatload (we're talking Cleopatra's barge here) of chocolate as a coronation present. Now she's a prime suspect. Where's a knight in shining armor when a Fae damsel in distress really needs one?
Enter Guber, Fae of royal blood, Human-phile and techno-geek. Mysteries and gizmos to test for substances harmful to Fae life and limb are right up his alley. Epsi is the prettiest damsel in distress that he's ever seen--and she doesn't think he's weird.
Guber has been living in the Human realms for decades to avoid both the Fae who want to reinstate the hereditary royalty and those who want to eradicate anyone with the slightest trace of royal purple blood. Both of them are on Guber's tail, and could focus on Epsi at any moment.
It's a good thing they have an entire warehouse of possibly poisoned chocolate to use as a weapon.