Mitsuka Souji is a first year high school student who greatly loves the "twintails" hairstyle. One day a beautiful girl, Thuearle, who comes from another world suddenly appeared in front of him and gave him the power to transform into the twintails warrior TailRed. Now Souji, with the help of his childhood friend Tsube Aika who can becomes the twintails warrior TailBlue, must fight in order to protect the peace on earth.