"Don't worry about his opinion of you. Unless you become his slave, it won't matter one bit. 

Viridian, do you have a preferred name?"

"-Mazen Broggs, scarlet*. And, uh, do you have a preferred-"

*scarlet = a formal term of address for reds**

**reds = the subset of humans with red hair and red eyes

"Arly welt-Karilya. How strange is this situation for you, Marc?"

Anyone's opinion of him being entirely unimportant sounds unlikely, but it's really not the question to focus on.  The slavery is, but doesn't seem a good first choice of topic either - he'd like to get a slightly better idea of what this world is like before he starts trying to talk about something this high-stakes.  And he should really just answer the questions of people who have a better idea of what's happening than he does.

"Entirely.  I've never seen a person with green hair, or a building this tall.  Which probably doesn't make any sense to you, does it?"  Maybe he's wrong about that and they do have some sane explanation for how he's here.  But it seems unlikely.

"It's the sort of thing that might happen in stories. When it does happen in real life, there are processes and procedures for handling it.

Does someone own you already, where you come from?"

If there are processes and procedures then they probably know better than he does about what to do here, and he should cooperate with that until he's sure it's going wrong, and try to see the sense it makes, no matter how strange it all seems.

...

That question causes him to make a variety of interesting faces, insult and bafflement and yearning and regret.  It's a long moment before he manages an answer.

"Does someone--  What a question to ask a man."  He takes a breath, exhales, shakes his head.  "I... I do not know what to tell you.  Nobody is a slave, where I come from.  But does my king own me, if I knelt and swore to serve him until the gates of death, and spent my life doing it?"

He has no idea what it will mean, to these people.  But he will not pretend he didn't.

"The most convenient thing-"

"The thing you want."

Arly welt-Karilya whirls on Mazen Boggs.

"The thing I want," she says, silky smooth and with a shark-toothed smile. "Yes. Is that a problem, viridian Boggs?"

"I want Marc to know his options, scarlet welt-Karilya."

He shoots the green-haired man a grateful look, but a concerned one, too.  If the woman is going to be angry about this - and it's important to know, that she is - Marc would much rather it be at himself.

"I would also like to know my options," he interjects, his voice sharp where a moment ago it was nothing like it, "scarlet welt-Karilya.  And I would like to know what the right thing is here, not just the convenient one."

Mazen knows when to push someone who could chew him up and spit him out- rarely, and only in defense of something important. 

He's used up his most valuable tool already- reminding her there are witnesses.

She nods, briskly.

"As soon as our government discovers you, they will want a definition for you. There are many ways this might be done- you might be declared a member of a foreign planetary government, which would trigger diplomatic channels. You might be branded a criminal and sent on your way, carefully monitored. You might establish yourself as a local citizen in an unfortunate situation- in which case, you will need to be easy to identify as a slaver or a slave. Those are your options."

'You don't act like a slaver' is unstated, but she'll state it if Marc seems to need it.

She's not angry at him.  Why not?  Kindness to someone in a difficult situation, or a decision not to alienate someone she might want something from?  He doesn't understand these people nearly well enough to tell.

He doesn't understand this society nearly well enough to choose between the options she gave him, either.  ...He doesn't like any of them, though he's trying to defer that judgment until he knows enough to be sure he's not wrong in it.

"How is... being a slaver or a slave... chosen, for people born here?  Which are you?"  He glances at Mazen to include him in the question, but he has a more confident guess for him.