Essam 293, of the Sulp Niar pool, was a Yeerk who helped Edriss 562 start the Yeerk invasion of Earth. At some point before this mission, Essam had been a Sub-Visser, but was demoted out of the Sub-Visser ranks for letting a group of Hork-Bajir escape.
While in human host bodies, Essam and Edriss develop a relationship which leads them to having two children while they were controlling the human bodies: Madra and Darwin. Essam didn't want to have them made into Controllers and died by kadrona starvation rather than let them do that. The human survived and is a street loony that Visser Three calls in during Visser One's trial. in the book VISSER he was in love with Edriss562