Thouars

Thouars (トゥアール Tuāru?) is an unknown girl that comes from another world, who claims Sōji Mitsuka to be the only man with the most potential of using Tail Gear, and entrusted him one to fight the monster, by transforming into Tail Red. She also gives Tail Gears to another chosen twintailed girls who has potentials, and oversee them.

On Volume 2, she joined Yōgetsu High School and form the Twintail Club together with Sōji and Aika.