Ikki Kurogane walks in on Princess Stella Vermillion changing clothes. A duel will settle the matter, but Stella raises the stakes, obligating the loser to lifelong servitude.

Ikki’s sister, Shizuku, enrolls in the school and causes quite the commotion upon seeing him. With Shizuku's arrival, Stella learns more about Ikki’s history.

Shizuku invites Ikki to go shopping, but is annoyed when Stella joins them. Ikki meets Shizuku’s roommate, whose device helps the group as they encounter some serious trouble!

Ikki’s first official match approaches! Unfortunately, he and his opponent, Shizuya Kirihara, have a history. Worse, Kirihara has the immediate upper hand due to his device.

As a result of his selection match performances, Ikki gains an unexpected following. Kagami gives Stella some advice that may save the princess and Ikki from parting ways.

Another student wishes to be Ikki’s pupil, but doesn’t quite know how to ask. Despite her initial awkwardness, Ayatsuji proves to be a hard worker and talented with a sword.