Also known as: アーティ・レイン
The magical girl form of Doumyouji Kotetu
She fights with a hoop that contains the power of water.
Her Artygear is the only gear created directly by her father, who developed it, and despite being the earliest type, it still has the strongest abilities.
For that reason, it is also known as the "Original Gear."
Kotetu's own abilities are not only outstanding, but also due to his training since childhood and his extensive experience in actual combat, making him the "strongest magical girl" in both name and reality.