Jameson by Anna Hackett

We survived the invasion and beat the aliens. But they left something behind…

Humanity is rebuilding after a devastating invasion. But the growing towns all have walls to protect them from the monsters. Created in alien labs, the monsters hide in the swamps, rivers, and forests—breeding, mutating. Every now and then, they crawl out of the shadows.
That’s where I come in. I’m Jameson Steele, the leader of Hunter Squad—the toughest group of soldiers in New Sydney. It’s our job to keep people safe and secure.
We’re the monster hunters.
When I get a panicked call from my childhood friend, Greer Baird, my usual cool goes out the window.
Greer’s an engineer working on a huge dam project that’s vital to our water supply. There’s a giant, deadly monster in the lake, it’s killed some of her people, and she’s in danger.
I’ve wanted Greer for a long time, but she’s too good for me: too smart, too driven, and out of my league.
But there is nothing I won’t do to protect her.
No monster I won’t hunt down to keep her safe.