The whole point of the story was to keep things vague so I totally get how there's no clear facts. Sensei must have intentionally left everything laid out in bits and pieces so that we sort it out by ourselves. From what i can tell, Aruse is Grey. There's too many things that Grey said that fit Aruse too much for him to not be the same guy. He couldn't have put or had that beauty mark himself before Aruse was even mentioned by Sudo. And the "you won't even sleep with me" and "I hate being indebted to others". Also one of his disguises in the last chapter had the same shade of hair as Aruse, just older. Probably his real hair color? He just lied about not being Aruse either due to his nature or because in the past, Sudo wouldn't sleep with him. Besides, why would the author introduce a character (Aruse), give him his own bg story and connection to the protagonist if he didn't mean crap to the story? Well, that's just how I see it.
The whole point of the story was to keep things vague so I totally get how there's no clear facts. Sensei must have intentionally left everything laid out in bits and pieces so that we sort it out by ourselves. From what i can tell, Aruse is Grey. There's too many things that Grey said that fit Aruse too much for him to not be the same guy. He couldn't have put or had that beauty mark himself before Aruse was even mentioned by Sudo. And the "you won't even sleep with me" and "I hate being indebted to others". Also one of his disguises in the last chapter had the same shade of hair as Aruse, just older. Probably his real hair color? He just lied about not being Aruse either due to his nature or because in the past, Sudo wouldn't sleep with him. Besides, why would the author introduce a character (Aruse), give him his own bg story and connection to the protagonist if he didn't mean crap to the story? Well, that's just how I see it.
Anyway. Those are some damn incompetent police.