Woman who helped Verad steal the Dax symbiont out of loyalty and love, then turned against him when the joining changed him.
Mareel is the companion of Verad, an unjoined Trill, in Invasive Procedures. A former prostitute whom Verad had befriended early in life, she boards Deep Space Nine with him and two Klingon mercenaries during a plasma storm and easily outfights Kira when the major tries to surprise her.
As Verad forces Bashir to transfer the Dax symbiont into his body, Mareel watches the man she loves become someone she no longer recognizes. She stays loyal at first, but finally decides to help Sisko, and Verad is stopped before he can escape.