For a reverse harem academy book this is not a bad one.  
There is nothing new in these books but overall the writing isn't bad and the characters have some depth to them. 

The bonds are the difficult part to write as believable.  Writers either jump on establishing them too quickly or they don't spend enough time to make each bond seem equal and each character relationship seem fully realized. 

I think the author does a pretty good job here with her characters as well as create a story that has enough tension and adventure to keep the momentum even throughout the series