To collect energy for the Makaiju
Not to be confused with the Sailor Animamate, Sailor Aluminum Seiren.
Seiren was the eighth Cardian. Ail and An send her to gather energy for the Makaiju.
Ail and An summoned Seiren at T-A Girls' Academy's cultural festival after raising the audience's energy level when Sakurako Ougi convinced them to dress up as aliens for the fashion show. Seiren made everyone fall asleep with her powder but Usagi, Ami, Rei, Makoto, and Minako escape the attack. Seiren used her hair to drain Rei's energy but the others transformed and stopped her. Seiren began draining their energy but Rer transformes into Sailor Mars and stopped her attack with Fire Soul, however, this was not enough to destroy her. Just then, Moonlight Knight appeared and stopped Seiren's attack. When she swung her tail and knocked over the music that Rei worked so hard on, Sailor Mars used a new technique, Fire Soul Bird, to damage Seiren and restore the other Sailor Senshi's energy. Sailor Moon then destroyed Seiren with her scepter.
She was a mermaid with pink hair that coud extend and constrict enemies to drain their energy. She could also shoot blasts of water from her mouth, fly, and use a pollen powder that can put anyone who touches it to sleep.
- Seiren could only repeat her name in the original Japanese anime, but in the DiC English dub, she is capable of speech.