I'm wondering in this conversation if Synx knows about Frux meeting Muts, perhaps saying that given the way Muts' mother looked, nobody was surprised he turned out to be so "monstrous", and perhaps she is using this as an opportunity to try to spy on Wrex, while Wrex is trying to use Muts' relationship with Frux to try to spy on Synx.
Maybe Frux accidentally spills some of the soup and Synx says not to worry, it's just some left-over officer rations.
When Frux flips through the book we show that many of the pages have been censored.
During the dinner Synx says she is pleased to see Frux still reading that book she gave Frux earlier (Watership Down), Frux says it's fantastic but doesn't understand why Fiver and the others don't just beg for the human's compassion, after all humanity isn't cruel. Synx says they're only non-feral with each other, the humans can't understand them. Frux replies that doesn't make any sense.
This leads to the conversation where Synx says Rosewater is littered with these inconsistencies. Synx once read another story, purportedly a compilation of human history, it said the whole world had gone to war, not once but twice, and the second time the fighting only ended when humans found a mysterious metal underground, one imbued with vast, unimaginable power. They forged it into a weapon that could destroy entire cities in a single strike, it would curse the land afterwards, poisoning all those who entered it for a generation. The humans were so terrified by what they created they vowed never to use it again, or else there might not be anyone left for the next war.
Frux is in awe and asks "And did they?" but Synx just laughs, explaining none of that actually happened. Magic like that doesn't exist. The whole world doesn't go to war and obviously not twice. The rosewater stories were obviously meant to educate and entertain, but they can't be taken seriously. There's no consistency between them, the rules of the universe change from one story to the next. It's too arbitrary, too contrived, too bizarre and disjointed, the most inconceivable events happen just because it's convenient to the plot. There's no internal logic about it.
At one point Synx complains that anything bizarre or fantastic about the Rosewater worlds is just explained away as being part of the universe. Frux argues that maybe things they consider magic are just normal in human's world. This is where Synx argues that there is no human world because it's totally inconsistent.
But Frux doesn't believe her, after all aren't they speaking human languages right now? Don't they develop human technologies?
Synx asks if Frux has ever seen a human. No? Nobody has, theyr'e as mystical as dragons or hybrids or pokemon. Synx knocks on the table and explains this is real, the warren is real, but Rosewater only exists in the imagination. Whoever invented Rosewater was no doubt brilliant, perhaps the most brilliant animal to ever live, but they're still just stories.
After the conversation ends, the lights are turned on and we realize a Fox has been behind Synx, watching the entire time. He calls Frux an interesting case, she displays neither the accelerated aging or cognitive deterioration associated with her bloodline, calls her a regression. When he asks to purchase her Synx refuses, and we have the conversation where Synx mentions she once had a son, called "Muts". When the fox presses further Synx coldly replies that she didn't hire him for psychoanalysis and she doesn't recall him ever offering his services for free. He says, no of course not, that's not why he's here, with a toothy grin. He asks when she would like him to begin. Synx replies "Immediately."