The Cursed Rune by G. Bailey

Two years at the academy. Four alpha jerks. One badass thieving assassin stuck in the middle of them all. A forgotten and deadly curse.

Daesyn Heartlocke wanted nothing more than to finish her latest assassin-for-hire job, get her boss off her back, and get back to hanging out with her talking monkey.
But when the job goes wrong, Daesyn finds herself being dragged into her father’s world of the reapers. The world she ran away from, the world that offers nothing more than darkness.
What’s worse? To stay free and, most importantly, alive, Daesyn has to swap places with a student who is due to go to a crazy academy.
Royal Reaper Academy is a two year test, and only one student comes out alive.
If you can make it to the end, you are given the throne of the reapers.
No pressure?
Daesyn has no choice but to win. Luckily for her, surviving is what she does best. Even if the other students are trying to kill her.
Outside the realm of the reapers, another world awaits Daesyn, and it calls home all those who escaped.
But Daesyn can’t escape what’s in her blood. Or the curse that is destined for her that has just been awoken.