[Yeah, well... he's not planning to forget about it. It sort of implies that his presence means something to Billy, doesn't it? That's worth remembering.]

That's a good idea.

[On a different occasion, he might've offered to join him, but he doesn't need his wounds aggravated... or to be puked on.]

You can--check my back later, if you want. When you're feeling better.

See if anything weird's grown there.

[He flashes a little smile. That's not a weird thing to offer, right?]