Rob Thurman - Cal Leandros (#1-9)

Nightlife (Cal Leandros #1)
In New York, there's a troll under the Brooklyn Bridge, a boggle in Central Park, and a beautiful vampire in a penthouse on the Upper East Side. Of course, most humans are oblivious to this, but Cal Leandros is only half-human. His father's dark lineage is the stuff of nightmares-and he and his entire otherworldly race are after Cal.

He and his half-brother Niko have managed to stay a step ahead for three years, but now Cal's dad has found them again. And Cal is about to learn why they want him, why they've always wanted him...

Moonshine (Cal Leandros #2)
After saving the world from his fiendish father's side of the family, Cal Leandros and his stalwart half-brother Niko have settled down with new digs and a new gig-bodyguard and detective work. And in New York City, where preternatural beings stalk the streets just like normal folk, business is good. Their latest case has them going undercover for the Kin-the werewolf Mafia. A low-level Kin boss thinks a rival is setting him up for a fall, and wants proof. The place to start is the back room of Moonshine-a gambling club for non-humans. Cal thinks it's a simple in-and-out job. But Cal is very, very wrong.

Cal and Niko are being set up themselves-and the people behind it have a bite much worse than their bark...

Madhouse (Cal Leandros #3)
Half-human Cal Leandros and his brother, Niko, aren't exactly prospering with their preternatural detective agency. Who could have guessed that business could dry up in New York City, where vampires, trolls, and other creepy crawlies are all over the place? But now there's a new arrival in the Big Apple. A malevolent evil with ancient powers is picking off humans like sheep, dead-set on making history with an orgy of blood and murder. And for Cal and Niko, this is one paycheck they're going to have to earn.

Deathwish (Cal Leandros #4)
Half-human Cal Leandros and his brother Niko are hired by the vampire Seamus to find out who has been following him - until Seamus turns up dead (or un-undead). Worse still is the return of Cal's nightmarish family, the Auphe. The last time Cal and Niko faced them, they were almost wiped out. Now, the Auphe want revenge. But first, they'll destroy everything Cal holds dear...

Roadkill (Cal Leandros #5)
Once, while half-human Cal Leandros and his brother Niko were working on a case, an ancient gypsy queen gave them a good old-fashioned backstabbing. Now, just as their P.I. business hits a slow patch, the old crone shows up with a job.

She wants them to find a stolen coffin that contains a blight that makes the Black Death seem like a fond memory. But the thief has already left town, so the Leandros brothers are going on the road. And if they're very, very lucky, there might even be a return trip...

Blackout:
When half-human Cal Leandros wakes up on a beach littered with the slaughtered remains if a variety of hideous creatures, he's not that concerned. In fact, he can't remember anything-including who he is.
And that's just the way his deadly enemies like it...

Doubletake (Cal Leandros #7)
Half-human/half-monster Cal Leandros knows that family is a pain. But now that pain belongs to his half-brother, Niko. Niko's shady father is in town, and he needs a big favor. Even worse is the reunion being held by the devious Puck race-including the Leandros' friend, Robin- featuring a lottery that no Puck wants to win. As Cal tries to keep both Niko and Robin from paying the ultimate price for their kin, a horrific reminder from Cal's own past arrives to remind him that blood is thicker than water-and that's why it's so much more fun to spill.

Slashback (Cal Leandros #8)
I stopped and let them circle me, first because it was intriguing and, second, because, honestly, what could they do? Only knives, but all armed, and that made them even more interesting. Interesting. Fun.

Playtime…
Taking on bloodthirsty supernatural monsters is how Caliban and Niko Leandros make a living. But years ago—before they became a force to be reckoned with—the brothers were almost victims of a very human serial killer.

Almost.
Unfortunately for them, that particular depraved killer was working as apprentice to a creature far more malevolent—the legendary Spring-heeled Jack. He’s just hit town. He hasn’t forgotten what the Leandros brothers did to his murderous protégé. He hasn’t forgotten what they owe him.

And now they are going to pay… and pay… and pay.…

Downfall (Cal Leandros #9)
I let it go—all of it. Everything I’d been saving up all my life, building and growing inside me, too much to hold in one half-human body. It pushed and fought to be free with a force that turned me into a bomb with a timer vibrating on zero. I was free.

But so was everything I’d fought so hard not to be…

Brothers Cal and Niko Leandros know trouble when they see it—and then proceed to wipe the floor with it. But now it seems their whole world is falling to pieces. Cal’s nightmarish monster side is growing ever stronger, changing Cal physically as well as mentally. Which is exactly what Grimm—Cal’s savage doppelgänger—wants. And when a covert supernatural organization decides that it’s time to put Cal down before he threatens pretty much everything else in existence, the brothers find themselves in a fight they actually might lose. But the dark temptations Cal has denied all his life may prove to be exactly what can save them.

Even if he must fall forever