Honestly, Butcher begging -- or even behaving himself -- would just be unbearably awkward for the both of them. This works much better as a friendly back-and-forth.

"What, torture?" He pushes the questionable shirt aside, taking a slow breath before starting to draw a series of small cuts over Butcher's left hip bone. They may loosely resemble the letters H and L. "Never done it in such a structured environment. Orrr with a knife."

Sorry Butcher, you're gonna have to grit your teeth through his amateur ways.