Winloss was a hunter by trade and the spouse of Nokk. He was also known to carry an NN-14 blaster pistol.
Winloss and his wife, Nokk, were in the employ of Doctor Aphra. Aphra made contact with the hunters via hologram. She guided Winloss and Nokk through a series of perilous traps under the false pretense that she needed them to capture a creature for her employer. Aphra's real intention was to get out of the Shadowfang Beast's stomach before she was digested.
Winloss and Nokk, under the employment of Cornelius Evazan who was disguised as Princess Leia Organa, traveled to Milvayne with the intent to kill Aphra and disable Triple-Zero.
When Aphra, Triple-Zero, and Vulaada Klam, who had been attacked by a revived Tam Posla while riding on the qaberworm Gurtyl, Winloss and Nokk showed up. They shot a harpoon through Posla, and disabled the rebuilt BT-1. Aphra and Triple-Zero were able to get away from the hunters, who took BT-1 with them and continued their pursuit.
Some time afterward, after Aphra had repaired Triple-Zero, the hunters tried to capture their prey. Nokk was sent on a chase through the Milvayne traffic. As part of their strategy, Nokk was seemingly shot down by BT-1, which lured both Triple-Zero and Aphra into a trap when they tried to reach the astromech droid. After being shot down by the Coalition for Progress, the hunters' starship started to plummet, and Winloss and Nokk ejected, escaping the crash.
After the ship crashed, Aphra was interrogated by Captain Okma of the Coalition for Progress, who was later killed by Triple-Zero. Sometime later, Winloss and Nokk came back to Aphra, ready to kill her, but they decided to let her live, saying that they preferred hunting more challenging prey.
Later on, Winloss and Nokk located Evazan and his associate Ponda Baba with the assistance of Professor Prexo. They disarmed the proximity bombs inside Aphra and Triple-Zero, as well as the technology Evazan had been using to broadcast the events to the entire planet.