Probably more along the lines of 3.75, to be precise. I really wish GR did 1/2 stars at least. 
 May be slightly spoilerish... 
 First, one of the best parts of the book was the the "bad" words. Fak being one of them. I am always trying to find new words to say in place of the really bad words, and I think Fak might just be a good replacement! 
 I liked Soulbound. A lot actually. Kaya was a fierce girl, very determined. A little bit of a dumb dumb in the boy department, but that seems to be a trend. Maddox, Kaya's guard, was definitely one of my favorite characters. She was the comic relief. Then there were the boys, Trayton and Darius. I wouldn't call it a love triangle, which was wonderful, but I can definitely see it heading in that direction for Soulbroken. I think, though, that it may be one love triangle that I completely understand. Anyway, Trayton was a prick. Completely, without a doubt, no question about it. Others may disagree with me, but that is just my opinion. First, would you be okay if you walked in and found some girl sitting on your mans lap? I wouldn't. I would be pissed. His excuse? She is persuasive. Ummm, heck no. No way. He doesn't give two shits about what Kaya wants, who she is. And when she goes behind his back to learn to defend herself, he turns on her and starts spending time doing who knows what with lap girl, instead of talking to Kaya. He also turns her in, which is bullshit. And Kaya? Yeah, she forgives him. She does stand up for herself, but she doesn't make him answer to the things that he did wrong. Not Okay! Moving on, I love Darius. Quiet and mysterious, harsh but for good reason. He is clearly the winner in the dude department. 
 The story is about Barron's, the fighters, and Healers, who are Bound to the Barron's and follow them to battle in hopes of being able to heal them with a touch. Most are raised learning about the roles of their kind. Kaya was not raised in the schools. She was raised by her parents, who were both Barron's which is a big no-no. She is basically threatened into attending the school, and being Bound against her will. She goes to protect her parents. Awwww! Healer's are not allowed to train to fight against the Graplar's who are the enemy. Very scary creatures, Graplar's. Kaya doesn't take lightly to being told no about learning to defend herself, and I can't blame the girl. In her mind, Healer's get treated like servants, and she hates it. So, she does something about it. She turns into a fierce little fighter, and that makes me so proud. 
 The story itself was a good one. The ideas are new, and intriguing. I enjoyed it very much. The only problem that I had was that sometimes the pacing was a little slow and I found myself getting bored. That being said, when the pace picked back up, boredom flew out the window. I was engaged, and I definitely felt a connection with Kaya and Darius and Maddox. The scenes with these guys were always the best. 
 All in all, I enjoyed the ride. I definitely can't wait to see what happens with Kaya and company in Soulbroken. Heather Brewer is a great writer, and Soulbound made me a fan. On to Vladimir Todd. 
 Sorry if I rambled. Sometimes that happens.