In his haste to catch up to the company the next morning, Bilbo had totally forgotten the strange two dwarves, or shadows-of-dwarves (as his mind had started calling them), from his kitchen. But after he was finally shoved on a pony, laughed at by the majority of the Company, scowled at by Thorin and consoled by Gandalf, Bilbo finally noticed the odd two dwarves amongst the rest.
After seeing them the night before, he had half expected to see them walking; but seeing as Thorin had insisted that he (Bilbo) ride, he was only mildly surprised to recognise the young blonde and brunette on two ponies towards the end of the line.
Once again, Bilbo noticed they were not like the others. The dwarfs did not all come across as forceful as Thorin, but they still all rode ahead with a clear sense of purpose: they were heading towards something. It took him a few miles to label the difference: the main group of dwarves were traveling somewhere, but the two younger dwarves were only following. It was all in their body language: hunched shoulders, no observable conversation, wary glances. It wasn't that they didn't look around and take notice of their surroundings; actually in some ways they seemed more aware than the others. But instead of just admiring what was around them, Bilbo swore that they seemed to be almost feeling it.
"You've noticed our two tag alongs, you have."
Bilbo jumped in his saddle when he realised that Balin and Bofur had come up alongside him.
"Sorry?"
Bofur jerked his head backwards. "Fili and Kili back there."
Bilbo shrugged. "I didn't know their names. They didn't come inside last night."
Later, he was sure there was a flash of something in Balin's eyes, but at the time it disappeared to quickly for him to identify it. "No, they wouldn't have."
It seemed like the two dwarves weren't going to say anything more, so Bilbo pressed them.
"Why?"
Bofur lazily raised one eyebrow. "Why didn't they come inside or why wouldn't they?"
"Both!"
Bofur sighed. "Do they have slaves in the Shire?"
Bilbo flinched and bit his tongue trying not to yell out to the whole group. "Slaves!" he hissed. "Hobbits don't have slaves!"
Then it clicked for him. Why the shadow-dwarves – Fili and Kili – were separate from the main company and given orders to do the worst jobs. Why Bofur was keeping his normally loud conversation so quiet. Why Balin looked almost ashamed.
Madly trying to process what he'd just learned, Bilbo stammered, "So who do Fili and Kili belong to?"
Bofur almost looked surprised that Bilbo had caught on so quickly.
"Thorin," Balin said quietly.
Bilbo nodded absently. That was what he was expecting – after the scene last night saying they belonged to the company would have been off.
"Is it… normal for dwarves to keep slaves then?" Bilbo asked, keeping his tone light. "I thought only men had slaves, is all."
Bofur and Balin exchanged meaningful looks, and Bilbo sighed internally. He could see this was one puzzle that would take a lot of tact to solve.
"Not normal, exactly," Balin started. "But in exceptional circumstances…"
"They're not criminals, if that's what you're worried about," Bofur added quickly. "They're not going to stab us in our sleep or anything."
"That's not what I'm worried about," Bilbo replied.
He felt Balin and Bofur fall back, but missed their second exchange of silent messages. He wanted to turn around and have another look back at the two (shudder) slaves, but at the same time he knew this whole situation was clearly on such a knife's edge that he didn't want to disturb things by crossing some undrawn boundary. None of the other dwarves seemed to be paying any attention to the slaves in the rear, and Bilbo didn't want to give Thorin another reason to dislike him by breaching some dwarf-slave code.
Perhaps Gandalf? Although he hadn't paid any attention to the young slaves either. Now that Bilbo thought back on things, Gandalf knew enough about the company to do a named headcount back at Bag End, so what were his thoughts about the slaves?
Bilbo shook his head out of his own thoughts. Asking himself more questions he didn't know the answer to was not helping him solve things at all. Remotely he found himself wondering why he was at all concerned about the circumstances behind two dwarvish slaves, but then he realised that he'd spent the last 10 minutes thinking about two creatures as only slaves – even though he'd known their names the whole time.
Fili and Kili.
Or maybe it was just that the whole situation was so unknown to him, and so obviously a touchy subject amongst the other dwarves, that the Took in him had to get to the bottom of the mystery. Either way, there should be plenty of time on the adventure to learn more.