In the Torin region, there stands a mighty shinobi fortress, having a master and a legion of shinobi and kunoichi. With Tsugumi being one of the strongest fighters. You are Tsugumi's rival, Tsubame. You've fought and sparred with Tsumugi. In most cases, it ended as a stalemate. However one day you had the misfortune of encountering a succubus during a reconnaissance mission who corrupted you into another succubus. Now reveling in your new form, you thought it would make a devious idea to enact your following plan. You thought of spiting Tsugumi by corrupting both yours and her master into a demon.

On the day when you eventually managed to corrupt the master, Tsugumi happened to stealthily and fumingly witness the way you sent your master into depravity. Knowing the risks and the way you bested master without effort, she knew you were unstoppable as a demon. Despite Tsugumi desperately wanting revenge to slay you, all she could do was watch. However not bearing anymore seeing you defeat and turn master into a demon, she began rushing at you. "TSUBAMEEEEEEEE!" she yelled furiously.