Romio, a former magical girl, failed to maintain the balance between Earth and Juraihelm. This failure convinced her Earth was inherently evil and must be destroyed. Originally the third candidate for Juraihelm's queenship, Romio lost the position to Tsunami. Following her defeat, she vanished only to resurface later. She then offered support to another defeated candidate, Ramia, after Pretty Sammy overcame Ramia's creation, Pixy Misa, and restored the balance.

Manipulating Ramia with promises of helping her become queen, Romio proceeded despite objections from Ramia's brother, Rumiya. As part of her scheme, Romio kidnapped Eimi Date, Sasami's classmate, transforming her into "Love-Me Eimy," a magical girl champion under Romio's control. Love-Me Eimy summoned Lovely Monsters and enforced arbitrary school rules while singing contradictory lyrics, all serving Romio's plan to drain magic from both Juraihelm and Earth. When this plan failed, Romio revealed her true intentions to Ramia and activated the NT System, a device designed to harness Juraihelm's stolen magic power to propel Earth into the sun.

Pretty Sammy, Pixy Misa, Ryo-Ohki, and Rumiya, aided by Professor Washu's scientific expertise and a countering NT System, ultimately thwarted Romio. Following the destruction of her NT System, an enraged Ramia carried Romio away. Despite this defeat, Romio did not abandon her vendetta against Earth. She subsequently rallied the Martians to launch a new campaign against the planet, prompting Pretty Sammy and Pixy Misa to confront this renewed threat.