Penno was a photometric projection of a Vori elder created by the Vori Defense Contingent.
After Commander Chakotay crash landed with shuttlecraft on a planet in the Delta Quadrant in 2374, he was brainwashed by the Vori to fight in their defense contingent.
Chakotay met Penno when he went into the Larhana settlement, where he lived with his granddaughter Karya. Penno welcomed Chakotay and cared for him, telling him to rest at a campfire. When the settlement was taken over by Kradin soldiers, Penno was sent off to an extermination facility.
Chakotay, who joined the Vori Defense Contingent after this experience, was later found by Tuvok. Tuvok brought him back to the Larhana settlement to prove the situation. At the settlement, Chakotay was again greeted by Penno who did not recognize Chakotay. (VOY: "Nemesis")