I'm looking for a beta reader myself and your premise sounds perfectly fun. I like to edit/beta, I'm pretty thorough. If you're interested enough in my premise to do a swap, I'd be more than happy to look at your work. Go ahead and PM me if you like.
My work: YA sci-fi/fantasy, 70k words.
It's been 18 years since the Exosan, horrifying and powerful creatures from myth and nightmare, descended upon civilization and brought humanity to the brink of extinction, before vanishing as mysteriously as they had appeared. Some people would say the world is a better place, now. A single government unites and protects all. Fantastic scientific initiative has put fledgling colonies on the moon. The future looks bright, but shadows linger. Where did the Exosan come from? Where had the gone?
What if they come back?
Elisha Cameron just wants to fight her way through one of the most selective private schools on the continent and keep the fact that she can turn invisible well under wraps, but when she discovers evidence of Exosan activity in her own neighborhood, that future becomes uncertain. She could go back to her normal teenage life and leave the secret war with the Exosan to the professionals. Except there aren't any professionals. There's just Elisha, and a handful of teenagers with a little Exosan blood running in their veins, a little magic at their fingertips.
The Exosan are regrouping. They're ready to come back and finish the job they started eighteen years ago.