Chief Edgar Willoughby was the sector quartermaster for Deep Space 9 in 2375. The name of his wife was Cynthia, and together they had two children: an eight-year-old daughter named Melissa, and a five-year-old son, Edgar Jr. He also went by the moniker of "Eddie".

When Miles O'Brien needed a new graviton stabilizer for the USS Defiant in 2375, he gave permission for Nog to place discrete inquiries regarding the availability of such a device. Nog gave Willoughby a bottle of Gamzian wine as a gift, and learned that it would take three weeks to acquire the replacement, which was too long.

However, Willoughby also informed Nog that the USS Sentinel had an extra stabilizer that they were willing to trade. Nog used this information to obtain something the Sentinel required and eventually acquired the stabilizer. (DS9: "Treachery, Faith and the Great River")