This is a side of Sherlock that Holmes is aware he also has. He, after all, is willing to die for Watson. To kill for him, or worse. And if it was for Watson, he would take torture without a fight. He has.

And he loosens the top buttons of his own shirt, and pulls it aside to show the gruesome scar in his shoulder.

"Oh yes. I do."

And that is all he says, before he assesses what he needs to do to get Sherlock by the throat, pinned to the table, where he can tear open the other man's shirt.