The Devil Went Down to Laughlin by Christine Pope

When you’re part demon, a simple ghost clearing should be routine. But when the ghost turns out to be bait, all bets are off.

Caleb Lockwood is finally settling into his new life in Las Vegas, flipping houses and keeping his demonic heritage under wraps. But after his friend and business partner Delia Dunne gets called to handle a haunting in the river town of Laughlin, his supernatural instincts scream danger.
Delia’s psychic abilities are growing stronger by the day, making her a target for forces that see her as the key to unlocking something far worse than a simple haunting. When she stops checking in from Laughlin, Caleb knows his worst fears are coming true.
Racing to the rescue with an angelic ally and a determined private investigator, Caleb discovers that Laughlin’s position on the Colorado River makes it the perfect prison — and the perfect weapon. A demon executive is using Delia’s amplified powers to strengthen an ancient gateway to Hell, and the only way to stop him is to venture into his underground lair beneath a casino built on mystical energy.

But closing a portal to Hell requires both human and demonic blood, and the enemy isn’t going down without doing his best to drag Caleb back to the underworld. With Delia’s life hanging in the balance and new guardians needed to protect the river’s power, some gambles are worth more than money — they’re worth everything.