At night, while Erstin is walking outside, past Nina's and Arika's room, she hears and spots Shiho Huit. Shiho asks Erstin if she really likes Nina, and after Erstin replies in shock, Shiho then hypnotizes Erstin with her Twirling Hypnotism Technique for one purpose - to beat Arika.
The day comes, and Irina Woods starts commentating the match, and explaining the rules. She explains that Fumi Himeno will decide judgement and the winner of the battle. As well as this, Irina explains that the winner will receive the Blue Sky Sapphire and will consequently become Mashiro's otome. Clutching Arika's doll, Mashiro looks at the battlefield in anticipation, along with the rest of Garderobe.
Fumi declares the start of the match by playing some music, and Arika and Erstin immediately clash. Miss Maria and Natsuki Kruger discuss who will win out of the two, while Shizuru comically decides to spend more time with Natsuki, to the latter's embarrassment. Erstin and Arika are equally matched, however, Arika unleashes a relentless assault, which Erstin dodges using dance and the music to her advantage, which Yayoi Alter and Miya Clochette express admiration over. Erstin then unleashes an assault of her own using her staff, which knocks Arika against a pillar, removing 5 HP points from her previous 30 HP points.
Back in the stands, Tomoe Marguerite compliments Erstin, while Nina expresses concern over Arika, and thinks about Erstin's moves. Meanwhile, Chie Hallard flatters Shiho, saying that her technique is as splendid as ever, to which the other says that she cannot wait for the match to be over. Miss Maria also compliments how far Erstin has grown.
Back in the match, Erstin uses her strength to knock a pillar on top of Arika, consequently trapping her. Erstin then begins to laugh and mock Arika, before deciding to deliver the finishing blow. Erstin's Coral GEM then begins to glow, as she activates her Miryoku, Super Bust Impact, which shocks the entire audience. She uses this ability to unleash a massive beam attack upon Arika, destroying most of the ground around her. This attack costs Arika 22 HP points, which leaves Arika with only 3 HP points left, while Erstin has all 30 left.
As the battle continues, so does the sideline drama, with every Otome in the crowd in absolute shock, especially Tomoe and Nina. Mashiro then proceeds to turn around, to which Natsuki inquires if "she" is running away again. Mashiro then rips the Blue Sky Sapphire from his neck, and states that if they want the GEM, they can have it, as long as they put a stop to the fighting. Shizuru then explains to a crying Mashiro that they are both chasing for that GEM, which she declares is a good enough reason for the two rivals to be fighting.  Natsuki then explains that Garderobe is for training Meister Otome, and how so little Otome are able to become Meisters. Upon hearing this, Mashiro expresses sorrow and worry for the two girls fighting for him. 
On the battlefield, an injured Arika trembles before Erstin, questioning how she got so strong. While Natsuki and Mashiro are discussing issues, Arika brings herself to her feet, and states that she cannot lose because she has to protect Mashiro.  Arika prepares to attack Erstin, much to Shiho's annoyance. As Arika swings her staff, Erstin effortlessly catches the staff and throws Arika through two pillars, deducting 1 HP point.  Arika remembers her tough past, which leaves her distracted, allowing Erstin to continue her attack. With just one hit point left, Arika gets hit with another pillar, and Erstin declares that she wishes Arika didn't exist, so that she could spend more time with Nina. While Mashiro cries on the sidelines, Arika struggles, and eventually breaks the pillar, declaring that she will not give up until all her hit points are gone. Upon hearing this, Mashiro runs away again. Natsuki inquires if she is running away due to sadness and fear, however, Mashiro glares at her and states that he isn't running from the truth. Mashiro jumps down the ramp and closer to the battlefield, and encourages Arika, stating that "his otome would never lose here".  Arika beams at Mashiro after he says this.
While the commotion on the battlefield is going on, Nina takes the opportunity to confront Shiho and Chie. She accuses Shiho of controlling Erstin. Chie asks Nina what she will do knowing this fact, and Nina replies that she will do nothing.  She also states that even if Erstin wins the match, Arika will surpass her some day. Shiho proceeds to command Erstin to finish Arika off, and Erstin immediately uses Final Bust Impact on Arika. Arika then remembers her grandmother's words, and counters by attempting to lift the attack. After declaring that she will never give up, Arika's gem starts to glow, and she activates her own Miryoku, Super Blue Comets. Using her Miryoku, Arika creates many after-images to deal a deadly assault on Erstin.  The damage reduces Erstin's 30 HP points to 0 HP points. Arika is declared the winner, much to Shiho's chagrin.
On the sidelines, Chie comically cuts Shiho's curled hair, and then proceeds to carry her away, while saying goodbye to Nina, admitting defeat. Miss Maria also compliments Natsuki's "foresight" for knowing that Arika would win. While Natsuki never foretold the outcome of the battle, she takes credit for Miss Maria's words.  Erstin is carried off in a stretcher, unaware of Shiho's mind control technique. Arika declares that she had fun with Erstin, and then celebrates with Mashiro. Suddenly, Arika's robe starts breaking, exposing her nude body underneath, to the absolute shock of Miss Maria. Due to this, Mashiro also nosebleeds and faints.
The following day, Arika and Mashiro visit the grave of Fumi Himeno, who tells Arika that she has obtained no points, and that she mustn't expose her bare skin in front of others, which leaves Arika crying.