This is really dumb and lazy. You invented a biotruth argument out of nothing and then asked me to go find proof of your assertion. Well, no. That isn't how people consciously make decisions normally. That's really fucking weird actually. The altruistic impulse is because people get distressed when they see other people suffer, not because they need to work out their family issues through a proxy. Of course, the point of that scene was just to make a creepy pseudo-familial association between the characters because anime is fucking creepy as shit.
I asked Arcness in chat and he said the colors got explained during his cheesecake dinner date (which I completely zoned out of). That being said, the player killer guild in episode four is clearly flagged orange, so again it's just more slipshod writing.it IS... what the fuck come on?