The suggestion has him sitting up straighter. He doesn't mind, so much, that the comparison is perhaps off-colour. He's just surprised that she might want someone more...Left Handed. Of course he isn't about to be some secretive assassin and spy for her, but still, the comparison is almost distressingly apt.

"Would you, perhaps, also require a Right Hand to balance the scales?" Amusement crinkles the corners of his eyes. "Cassandra, it would be my singular honour to perform these duties for you. Alongside you."