Qantus was a dark green Agori, one of Le Chiffre's servants, and a member of the Forgotten Tribe. He appeared to have stolen alien technology, what with him possessing a teleportation device and all that. Then again, it might have been provided to him by Le Chiffre. After all, nearly all the Forgotten Tribe Agori have been shown to have those...
Much, much later, Qantus was sent to deliver a message to Uterio di Armechio. The message didn't make Uterio too happy, so Qantus was thrown out of a window, drawn, and quartered.