It would have hurt less to hear Hannah admonish him! He'd have preferred that to this.  Her approval for shame he'd carried for so long.  Shame he'd felt immediately upon doing the deed, and shame he'd felt every time he'd thought of it these past decades.

He screwed up his face in abject bafflement. Vengeful, sharp-biting, snarling Hannah? She'd have helped them and done so gladly? She'd do so again and again.

"You can't know that!" he accused.  "How can you possibly know that? If it were me? Now? If I - I'd out their lights." He covered his mouth to silence his own dark words.

"No. I wouldn't have."

He realized now that he'd never be able to let creature die, let alone kill one.  He didn't even squash spiders.  Then why did Hannah's approval burn so sinisterly?

"You think I'm a fool," he said with a sheepish grin and an accusing finger.  "For feeling bad all these years? You know what would have happened to me had I been found out? Duty or not, I'd surely be in Azkaban. Healers can't be vengeful, but the Wizengamot can."

Perhaps Knox hadn’t received the response he’d expected. Perhaps his dramatic shame held little reasoning in Hannah’s eyes. Yet he was confused by his own beliefs of what he would and wouldn’t do. Hannah watched as he had a battle with himself over his own dark thoughts. She pulled her hand back from his, lips pursed as she debated what to say next. She shouldn’t have brought up the subject of him healing. She should have let it lie, continuing to wonder why he’d never told her about his skills.

Did she think him a fool? Hannah considered for a moment as the wizard stated the vengeful nature of the Wizengamot.

“And yet you are now part of them...” The words escaped before she could hold them back. She watched Greyfriar carefully for a moment before continuing. “You know what I think of you, old man. You’re righteous; you sit on your high hippogriff and think you know everything. It’s black and white to you. Now you’re telling me about a shame you’ve held for years. And a shame about what? Being unable to refuse to treat people. You are a fool if that still eats you up.”

With that, the witch stood back up and made her way to her shoes. She wobbled against the wall as she pulled the tall heels back onto her feet and grabbed her robes from over the chair.
“I’ll see you, Greyfriar.”

"I do know everything!" he boomed jovially and rose from his chair. A drunk Greyfriar was quick to move between past and present, melancholy and celebration.  He plod heavily to his little round-top door, preparing to let her out. 

"And I'm getting greyer and greyer as time goes on."  He bowed his head and indicated the silvery hair at his temples.  He grinned at his own joke.

"I'll see you, Bombay.  Happy nine thousand, one hundred and twenty-fifth day.