Please remember that this is just my opinion. You don't need to change anything, if you don't want to.
I want to start by congratulating you on making your story interesting. Your blurb immediately pulled me in. Then I read the first chapter, and I kept reading. Partialy because that's what I'm supposed to do, but also because I was asking questions, and wanted answers.
I also want to say good job on creating the characters themselves. Take Rose, for example. She has attitude. And that, I love. I can easily imagine what she says and how she says it. She also has her other side, the assassin side. It's always nice to see a character with different sides.
Just be careful of the Tenses. Like Past tense (He was, I thought, They said, ect.) and Present tense (I did, We go, they say, ect.). Also, the more detail, the better. Like when they enter the storage place, you could say that it smelled a little bit like blood, and as I looked around, I faintly saw blood splattered on the ground, coincidentally right behind the chair. It's just a little thing, but a bunch of small things add up to larger things :)
