Touka Akatsuki (朱月 藤果, Akatsuki Tōka) is the main antagonist of Gaim Gaiden: Kamen Rider Zangetsu. She was a servant of the Kureshima family and a childhood friend of Takatora Kureshima who transformed into Kamen Rider Idunn (仮面ライダーイドゥン, Kamen Raidā Idun).