Murid was a Youma owned by Jadeite. As part of the Dark Kingdom's continuing efforts to obtain energy, she posed as the mascot of the Dreamland amusement park, the "Dream Princess." In both her Youma form and her disguise as the Dream Princess, she could breathe out a red fog that would cause her victims to enter a waking dream state. Then, with the red apple she carried, she drained the dreaming people of their energy.
When Usagi, Rei, and Ami went to Dreamland to investigate the mysterious disappearances there, Usagi was enthralled by the Dream Princess, though Rei sensed a strange aura around her. Ami went to investigate her alone, but was caught in a dream and her energy was drained, though not before she realized that the apple the Dream Princess was carrying was what she was using to drain energy. Rei realized something bad had happened, and she and Usagi transformed and went after her.
When Sailor Moon and Sailor Mars first confronted the Dream Princess, she offered a flower garland to Sailor Moon, but it was actually a disguised snake with a venom that would turn the one bitten to stone. After the snake bit Sailor Mars, it then turned to stone itself. Sailor Mars freed herself from the poison using Akuryo Taisan, and Murid revealed her true Youma form. The two Sailor Senshi were caught by her dream-inducing powers, only freed by the assistance of Tuxedo Mask, and they and Luna retreated as they realized the Youma was too powerful for them alone.
The two Senshi found Ami, who was struggling to escape from Murid's powers, and she transformed into Sailor Mercury to assist the others. When all three of them together attacked Murid, they managed to destroy the Youma and the apple she carried, releasing the energy she had stolen.
(Source: Project WikiMoon)
