Sonko Fromm was the oldest son of the Annoo-dat Blue gangster Sise Fromm, the older brother of Tig Fromm, and a member of the Fromm Gang. As Sise's right-hand man, Sonko was assigned to a transport raid but botched it. He was imprisoned on the planet Umax but later freed by his father, only to be locked up in the dungeons of Sise Fromm's own palace on Annoo so that Sise could hear him wail in agony. Sonko's fate became widely known as a tale of Sise Fromm's temper.