Queen Nehellenia is the leader of the Dead Moon Circus, named after the Teutonic goddess Nehalennia. She makes her first appearance in Episode 148 of the anime and fully appears in Act 37 of the manga, though she initially appeared as a voice in a mirror starting from Act 35.
In the manga, she is portrayed as the dark mirror image of Queen Serenity, styling herself as the Queen of the dark center of the moon who made her presence known during the Silver Millennium. At Princess Serenity's birth celebration, Nehellenia confronted Queen Serenity, swirling with dark energy. The Queen used her Moon Stick to seal Nehellenia inside a dark mirror world forever. In retaliation, Nehellenia cast a curse that the Moon Kingdom would fall and the princess would never inherit her throne. Her dark magic ultimately brought about the end of the Silver Millennium. Over one thousand years later, a solar eclipse allowed her to spread her curse to Earth through infectious nightmares, aided by her minions, the Dead Moon Circus. Nehellenia still believed she was the rightful owner and heir of the illusory Golden Crystal and set out to steal it.
In the anime, Nehellenia is depicted as the dark mirror of the moon who dreamed of staying young and beautiful forever. Her kingdom was located on what she described as a lonely and cold asteroid. When she looked into an enchanted mirror, she saw herself aged and ugly, realizing her dream could never be attained. To retain her beauty, she consumed the dreams of her subjects, turning them into Lemures, the main monsters in the series, and forming the Dead Moon Circus.
