Mad Gass'kin was a Bothan male who owned and operated Mad Gass'kin's Used DroidNet. He ran an advertisement for his services on the DroidNet.[1]
In his advertisement, he claimed that his agents would procure whatever droids the buyer would want, and deliver to the client, so to protect Gass'kin.[1]
He also claimed that he was not "Mad", but that it was his actual name that happened to mean a certain way in Galactic Basic Standard.[1]
Behind the scenes
Mad Gass'kin's advertisement appears in the Look Sir, Droids! article in 2001's Star Wars Gamer 3.[1]
Sources
"Look Sir, Droids!" — Star Wars Gamer 3 (First mentioned)- The Complete Star Wars Encyclopedia