I'm reading along, and I get to this:
X: What hast been -- of what profession?
Y: A bone setter.
X: A bone setter!
Y: A bawd, my lord. One that sets bones together.
I'm not getting it. I get the idea that a bawd puts bodies together, and that bodies have bones, and Y has been carrying around his dead fiance's skull and all.
Is there more to the joke?
(The OED shows "boner" in the sense of an erection first in 1962. Bone-ache as a sign of STD is recorded in the 14th century, but that seems to be about whole-body bone aching, rather than sexual.)