Harrot requires your assistance. Locate Aria's couch, and send the coordinates back to Harrot.
Acquisition
When entering Aria's Bunker following the operation to gain the aid of the Talons, the elcor Harrot has appeared next to a Harrot’s Emporium terminal. In order to gain Aria's favor, Harrot asks Commander Shepard to retrieve Aria's old couch, which Oleg Petrovsky had thrown out of Afterlife after the Cerberus conquest of Omega.
Note that if Shepard refuses this mission, Shepard will not have the ability to alert Harrot upon encountering the couch.
Walkthrough
At the beginning of The Assault on Afterlife segment of the mission Omega: Aria T'Loak, defeat the Cerberus forces in the water treatment facility. When the bridge across the water channel is destroyed, raise the dam and cross it to the other side. Immediately on your right, there should be an access ladder on the side of the catwalk that descends into the part of the channel that was just drained. Climb down, and beneath the destroyed bridge are the remains of Aria's couch in a pile. If you interact with the couch Aria will ask: "Is that my couch?", and the mission will be completed.