Kai is kind of the Gary to our Ash. He feels an intense rivalry with Ren, rooted in their shared experience at the Officer’s Training Academy. While hot-headed and perhaps a bit childish, his determination to do the best and be the best make him a formidable soldier and earn him a mission similar to Ren’s.
While the main rival, his true motivations and allegiances are ambiguous. He doesn’t get a lot of screen time, but hopefully we have time to develop him adequately.