There's no need to even coerce the halfling into this. Bilbo wants Thorin. He's always wanted him, since he'd known what wanting could be like. The great hall of Erebor is cavernous, but there's no one here to see them. In the coming weeks, when the dwarves return, the upper niches will be filled and true privacy here will be impossible to get.

So why not have it while they can?

Bilbo, dressed simply in dwarven garb provided to him by Ori, about his size and shape already, climbs immediately onto the throne. Into Thorin's lap.

Oh...so dangerous. So... Incredibly blasphemous. His clever fingers start on the buckles keeping Thorin's stately tunic in place. "Come? I plan to. With you."