Souji Mitsuka is a first-year high school student who is obsessed with twin-tails. One day, a beautiful girl from a parallel world named Twoearle, suddenly appeared in front of him and gave him the power to transform into the twin-tailed warrior Tail Red. With the Ultimegil organization attacking the planet, Souji now must fight in order to protect the peace on Earth.

Nobunaga Shimazakias Souji Mitsuka ♂ (voice)
Sumire Uesakaas Souji Mitsuka ♀ / Tail Red / Solar Metca (voice)
Yuuka Aisakaas Aika Tsube / Tail Blue (voice)
Maaya Uchidaas Twoearle (voice)
Chinatsu Akasakias Erina Shindou / Tail Yellow (voice)
Mika Kanaias Worm Guildy (voice)
Yoko Hikasaas Iisuna / Anko Iisuna / Dark Grasper (voice)
Rie Kugimiyaas Strawberry Twin (voice)
Naruhisa Arakawa