Eimi Date holds the position of class representative for Umi no Hoshi Elementary School's class 4-3. She exhibits unwavering dedication to enforcing school regulations, often citing rule infractions even in unexpected locations beyond school property. This behavior includes threatening to report classmate Sasami Kawai for arriving via motorcycle, though her attention is diverted by Ryo-Ohki's sudden arrival. Eimi reportedly harbors aspirations of becoming an actress, yet her singing ability presents considerable difficulties. During choir practice for the school festival, classmates gag and tie her; later, during the actual performance, they cover her mouth to prevent her disruptive singing.

Romio transforms Eimi into the antagonistic magical girl "Love-Me Eimy" using remote control technology linked to an antenna on Eimy's head. This transformation aims to sabotage Tsunami's queen inauguration ceremony by attacking the school and destroying Pretty Sammy. While under control, Love-Me Eimy retains elements of Eimi's core personality, reprimanding others for breaking school rules—though she invents rules opportunistically. She hosts concerts featuring contradictory lyrics despite her poor vocal skills. Her summoned entities, "Lovely Monsters," replace Pixy Misa's "Love-Love Monsters." Offensively, she employs potent fireball magic capable of destroying buildings.

During the confrontation, Pretty Sammy initially retreats before returning with aid from "Overly Splendid" Oryo disguised as "Cool Red." After a battle within Pretty Space, Sammy destroys Eimy's antenna, freeing Eimi from Romio's control. Upon regaining awareness, Eimi expresses horror at her magical girl outfit's violation of school rules, declaring it the biggest mistake of her life. She displays distress through crying and pleads with teacher Mihoshi not to expel her, claiming no memory of the events while controlled.

Despite liberation from mind control, Eimi remains permanently stuck in the Love-Me Eimy costume, unable to revert or remove it. This causes ongoing distress; when Earth moves closer to the sun, she expresses a preference for death over dying in the outfit. Her family reacts with alarm at her appearance, and she becomes irritable when questioned about it. Gradually, Eimi exhibits diminished concern for her model student image, evidenced by sleeping in class. In the series' conclusion, she attempts to ask Pretty Sammy for help removing the outfit but receives no response. The costume remains her permanent condition.