Hum, that's a toughy. Khyros is a pretty complicated character when you get down to it. The only characters that spring to mind off-hand when I think about who may have inspired him are the Arthurian Galahad, despite not living up to the mythical purity of that figure, obviously. He also takes some cues when it comes to inner conflict from Shinmen Takezo from Vagabond. Physically, psychologically, and even personality-wise, the biggest influence I can think of from media that I've indulged in recently would have to be Yasuri Shichika of Katanagatari.
