He's finding it very difficult not to laugh. The only thing keeping him from it is the sword in Thorin's hand, and the very real concern that he might find himself skewered on it.
Still, it is quite impressive, Bilbo thinks, as he surreptitiously glances around the Throne Hall. The light from the torches makes the gold strokes on the walls shimmer, and from a distance it looks quite tasteful. Artistic, even.
The dwarves disagree, of course. After the moment of stunned silence when they first entered the room, the small group erupted with rage. The rest of them are still preoccupied with trying to melt the prose written in gold off the walls. From the sounds of it, they aren't succeeding. Thorin, however, hasn't moved from his place in front of the throne since he first read the words scribbled above them. Every now and then, the corner of his eye twitches, and Bilbo takes another step sideways. Just to be safe.
He wishes he were brave enough to take Thorin's weapon away.
He softly clears his throat. "It's not as bad as all that," and he means it to be a comfort, but Thorin whirls on him with such a ferocious scowl that he gulps.
"He defiled our sacred halls with-- this!"
Bilbo follows the angry gesture of Thorin's arm, and bites his lip, hard. The Elvenking thrust deep inside Thorin's body, and the dwarf moaned. "Ohhh, yes, harder," he hissed, and Thranduil smirked and tightened his grip on the muscled thighs.
"I'm sure Balin will find a way to remove it. Look, here he comes."
Balin's expression is grim, his brow covered in a light sheen. "He melted the gold with his own fire, Mahal curse him. Our flames aren't hot enough to return it to a liquid state."
The fingers holding the sword squeeze the handle. "I'll kill him," Thorin snarls, "that disgusting worm, I'll chop his head off and use it as a toilet, I'll rip his wings from his hide, I'll--"
"He's quite dead already, Thorin," Bilbo interrupts, and narrowly dodges the edge of the sword. Thorin doesn't even seem to realize what he's doing, and even Balin is quietly retreating. Dwarves, Bilbo thinks with a roll of his eyes. Can't rely on them for anything, really.
"Well, if you can't melt what's already on the walls, why not just cover everything in gold?"
Thorin stares at him as if he's mad, but at least he's not swinging his sword anymore. "That would take large quantities."
"I've seen your treasure," Bilbo scoffs. "There's plenty there. Besides, think how impressive it would look to future dignitaries."
A calculating look slides over Thorin's features, and the frown that has been in place since their discovery finally melts into a pleased smile. "That's very clever of you, Bilbo," he says. "Gloin! I need estimates for the amount of gold needed to paint the entire hall!"
As Thorin leaves to harry his financier, Bilbo turns back to the writing on the wall. Without Thorin there to glare at him, he can read the rest of it, and he doesn't bother suppressing his grin this time.
Thorin impaled himself on Thranduil's hard cock, a loud moan escaping his lips. "You feel so good," he whispered as he began to ride the elf splayed out beneath him. "I need you inside me."
"Such a wanton little princeling," Thranduil crooned, and Thorin threw his head back and moaned louder when Thranduil curled a hand around him. "Pretty little thing."
It's quite well-written, really, in Bilbo's opinion. A pity it will all have to go.
Most of the company have left the cavern, except for Bifur, who is staring at the writing on the other side of the hall. With a sly grin, Bilbo quietly shrugs off his satchel and digs through it for his notebook.
Maybe he can write some of it down before they start painting. After all, having some power over the King of Erebor won't go amiss.