with a nod to "Monty Python and the Holy Grail"
Varric followed up on the attack on the Hawke estate, using the odd absence of left arms as his primary lead in his investigation. Apparently the expired thugs were members from one of the many gangs of Kirkwall. This group, The Resilient Righties, was led by one who called himself the Black Knight.
The ever faithful mabari, Dog, of superior olfactory skill pinpointed the location of their hideout, leading the charge and cornering the Black Knight in a random old, abandoned warehouse along the docks. Strangely enough, he was the only member of the gang who did not have a right arm.
(The codex entry Hawke and Co. found in the larder stated that initiates would cut off their right arms as proof of their dedication to their cause…whatever that was.)
In a duel against Hawke, the Black Knight charged forward, his sword clutched awkwardly in his non-dominant left hand, and promptly got his arm chopped off at the shoulder. So he began kicking at Hawke instead. Their conversation went as follows:
"Look, you stupid bastard, you've got no arms left!"
"It's just a flesh wound."
The Black Knight soon died after due to severe blood loss.
Meanwhile Hawke still had not drawn up the courage to tell Sebastian of her feelings for him, but that was okay. The next time they had a moment to themselves, he'll be sure to tell her first.