He did seem really evil and cruel, but he was given away to Mountain Herd by his own mother which probably made him bitter. The flashback he had from his point of view was really sad. I also ship him with Larksong, their relationship is so cute!
Search
I think it was completely due to the way he was brought up. First, his dam sends him to MountainHerd. Second, his cruel grandsire uses him as a tool. So yeah, he's not to blame. I think his relationship with Larksong might just be what he needs :)