I have this idea in my head that while Clear was being designed, Toue had problems developing his personality and reactions, and sometimes Clear would be happy but look angry.So, to check if his physical reaction was appropiate for his emotions,Clear was given the ability of changing his iris according to his mood.
please keep in mind english isn’t my first languaje and spanish is SO different. like, you create sentences differently. if you want the bigger version just tell me! :D and you might wanna go check my other stuff.