Outer Space Outlaws

I wonder why all the Kalgurians are happy when someone's about to lose their life, like Millie. In my opinion they are selfish, careless, mean and stubborn because what if they lose their life and all the humans are happy I wish that would happen to all of them because then they would learn a lesson not to be happy when anything is about to lose their life or maybe like themselves, surely they wouldn't be happy when they are at risk of loosing their lives, or their families lives, or their friends lives. Also, I want to know why the author can't make the Kalgurians speak english. I know they are aliens but the book is not real and the readers will not understand what they are speaking about especially when they sing and dance and all that I do not know what they are saying and so do any of the other readers who buy the book.