Mareena was a Tholothian female mechanic residing on Al'doleem, the river moon of Al'doleem.
At some point, Mareena entered into matrimony with Jogg and together they had two offspring: Colli and his sister. Sometime years before the rise of the Imperial Era, the Jedi Master known as Kirak Infil'a compensated them for safeguarding his ship during his period under the barash vow.
In the year 19 BBY, Infil'a's return found her and Colli immersed in their work. She voiced her astonishment, noting that she hadn't encountered him for many years. He requested the return of his starship. She responded that it needed repairs, but it would not require excessive time, and inquired if he was pressed for time. Infil'a revealed that he was a Jedi, and that the Galactic Empire was hunting them. Mareena acknowledged hearing about the situation, explaining their uncertainty about his return and emphasized her unwavering belief in the Jedi's innocence.

Infil'a recounted his encounter with a Sith Lord who attempted to pursue him, but whom Infil'a eliminated personally. He then disclosed his intent to also eliminate the Emperor and reinstate peace throughout the galaxy. At that moment, Jogg emerged with their other child, inquiring about the situation after hearing voices. Mareena assured him that everything was fine and that Infil'a had returned. Following Jogg's expression of surprise, Infil'a instructed them to commence repairing the ship. Mareena agreed, but inquired if the Sith might seek them out, to which Infil'a affirmed that Vader was dead.
As Mareena and Jogg repaired the ship, Infil'a entertained them by demonstrating the Force on various materials. He shared his aspirations to rebuild the Jedi Order and his potential return to share its mysteries. Subsequently, he sensed Vader's approach and dropped the materials, causing concern among the family. When Mareena inquired about the cause, Infil'a dismissed it as insignificant and stated his intention to investigate.
Vader challenged him to a lightsaber duel. Initially, Mareena was unable to identify the figure, but Colli suggested that it was the Sith. Infil'a instructed them to return to the garage and repair the ship, but Mareena questioned his intentions, to which he responded by drawing his lightsaber and declaring his intent to defeat Vader. Mareena hurried back to the garage and resumed repairing the ship.
Thanks to Ki'rak's warning, the ship was ready for launch by the time the city began to flood shortly after, allowing her and Jogg to put their two children into the ship and save them from the waters despite Mareena and Jogg ultimately perishing from the flood.
Mareena possessed blue eyes and fair skin. She adorned herself with a Tholoth headdress. She maintained a positive relationship with Kirak Infil'a and did not believe the Jedi were traitors.
Mareena specialized in mechanics, operating a garage and assisting in the repair of Infil'a's ship.
Mareena's initial appearance occurred in Darth Vader (2017) 4, a canon comic from 2017 authored by Charles Soule and illustrated by Giuseppe Camuncoli.