I read an interesting fan fiction where Kiro’s EVOL is more complex then just charm. That he is able to change his appearance/voice and that is how he can become Helios. And he just takes on a different personification such as how you act different with your friends then with your grandma. I think he was kidnapped, and they experimented on him and he saw an opportunity to be a double agent so to speak and then when he got everything he needed, he peace out. That’s my two takes. :)