Nine
So Robin, Arthur, Charlie, Jay and... Faust. He eyes the man, wondering if he will be trouble. Arthur questions, correctly, if they could trust someone that won't tell his real name. Yet somehow the guy seems... frank? Nine's thinking on a better word when Robin says "It's been two centuries. No one left to care if you use your actual name."
She has a point... and what else can they do? Leave the man behind? Nine recalls the old motto: nemo resideo, no man left behind. He risked his life many times for that, and was saved back two or three times. No way he was going to act another way, be it two or two hundred years! Also, who knows, Faust may prove useful. Must keep an eye on...
Then Faust turns to him: "Just so we're clear, I take issue with you telling a kid go first. Not right."
Nine looks again at him, surprised. Few had the courage to speak that way to him, and he likes people that have the guts to speak their minds. "Look, I didn't tell her to go, I suggested she could be our best choice, and she agreed. Also, Robin's no kid. Can't you see by the look in her eyes? She's hurt, but won't let it stop her."
He moves to the door, where Jay's already waiting. "We will have many chances to talk, Faust, and I hope you speak freely. Be sure, I'll do the same. Now we should move." Nine waits by the door with Jay, watching as Robin and Arthur reach the recess where the door to the next room awaits. So far so good. Now they just have to open it.