The kisses get an involuntary shiver, but not a bad one, and he smiles a little to himself.

"Yeah, exactly."

After so many years being alone so often, he hasn't really had anyone pay attention to knots or tension, which means there's quite a lot of it. Which means that when Luke digs in, even though Cal's used to pain, it's enough for him to involuntarily hiss in response, though he keeps it quiet. He doesn't want to discourage it, because he knows very well he needs it.

Although Luke probably also knows he needs it.