Belongo was a nephew of Grand Nagus Zek.

In 2371, he was being held by Starfleet on Aldebaron III. Quark contacted Commander Benjamin Sisko while Sisko was on his way to Earth to participate in a conference on the Dominion situation. Quark reminded Sisko of Zek's role in establishing contact with the Dominion. Sisko also owed Zek a favor. (DS9: "Past Tense, Part I")

This character was only mentioned in dialogue.