An Eye for An Eye

"Hey Garrus, where did you learn that human saying?" Shepard asked offhand, as she recalled his use of the phrase 'an eye for an eye' when they took care of Sidonis. They were sitting the mess hall as the Normandy approached her destination.
"What human saying?" the turian asked in reply, obviously he couldn't tell which saying she was recalling with so little information.
"An eye for an eye." Garrus visibly stiffened.
Silence.

"Garrus?" the turian shook his head.
"I can't remember, sorry Shepard." Shepard smiled and patted him on the shoulder as she got up to head back to the CIC.
"It's okay Garrus. You avenged them good and proper." Garrus nodded, 'An eye for an eye indeed.'