La exposición familiar anual está literalmente a un día de distancia y Louise se siente bastante deprimida por eso. Saito no solo no tiene nada impresionante que presumir, sino que este año la Princesa también está observando, lo que lo hace aún más importante. A medida que se acerca la noche, comienza la desesperación ya que Saito no puede producir un acto digno de elogio. Un visitante misterioso repentino resulta ser la propia princesa Henrietta y se explica su relación con Louise. Al día siguiente, Saito intenta una presentación solo para ser arrastrado temprano por Louise. Al alejarse del escenario, son testigos de un robo en curso por parte de Fouquet y su golem de tierra. Al no poder detenerla, Fouquet puede huir con el legendario Bastón de la Destrucción.

Con la llegada de Wardes y Louise solos, se encuentran con el Príncipe Gales en una iglesia aparentemente desierta. Después de terminar el negocio, Wardes le sugiere a Louise que deberían casarse en ese momento. Confundida y repelida por la idea, Louise intenta rechazar su oferta, pero uno de los aliados de Wardes aparece con un anillo de control mental, lo que la obliga a aceptar. Con el Príncipe como ministro, el matrimonio continúa y casi se completa hasta que Saito irrumpe en la iglesia. Sacando a Louise de su trance, Saito se apresura a rescatarla. En respuesta, Wardes mata al príncipe Gales y revela que, de hecho, está involucrado con los rebeldes que luchan contra el gobierno de Albion llamado Reconquista.

Saito sueña que regresa a Japón pero cuando va a buscar a Louise y no la encuentra se pone a llorar y a decir que un Japón sin Louise no seria nada y cae al piso despertando a Louise la cual le agradece por no haberse ido y por haberse quedado a ayudar en la guerra y le dice que ya no lo tratará mal y que vuelva a la cama.

Agnes se reúne con Henrietta para informarle que el Director de la Academia, Lishión, es el infiltrado solicitando su arresto, sin embargo, la princesa dice que aún no hay pruebas suficientes por lo que es mejor tenderle una trampa.

Las fuerzas aliadas de Tristain abandonan desesperadamente South Gotha, puesto que fue dominada por los rebeldes. En el puerto de embarque el obispo le pide secretamente a Louise que sea el anzuelo, debido a que se acerca un ejército de 70 mil hombres que si no son detenidos llegarán pronto al lugar de huida.

Louise has a nightmare where she loses the ability to cast magic. Awakened, she goes into the forest to attempt to cast explosion. Saito finds Tabitha reading a book, and she began to teach him the words, but Louise interrupts, telling Saito that she can no longer use magic. Tabitha saids that she will protect Saito since Louise is unable to do so. In Tristan, Henrietta dispatches the Ostland and Colbert to rendezvous with Saito, carrying a type of cannon (which seems to be a German Flak88 from WW2), and Agnes offers the assistance of the Musketeer Force. Silently, Colbert hopes the weapon will not be needed. Saito, under Tabitha's guidance, learns to read quickly, while Louise broods over her inability to cast magic. Overhearing Tabitha telling Saito that under the influence of Gandalfr, the heart will experience changes, Louise wonders if Saito loves her because of Gandalfr's influence. Just before crossing the border, a Square-class golem, with Sheffield on its shoulder, lands in front of the carriage and blocking off the route into Tristan. Slyphid and Tabitha take to the air, in order to lead Sheffield away. Guiche, Kirche and Tabitha's attacks prove ineffective against the golem, which is protected by Counter, but they manage to halt the golem's advance with their spells. Saito realises her objective is Louise, and tells her to stay back, but she jumps out of the carriage as Malicorn pulls it back. She is grabbed by the golem, who began to crush her unless she uses her magic. Saito's attacks are easily stopped by Counter, and Louise decides to sacrifice herself for her friends. Saito leaps to attack the golem again, and this time, his attack damages the golem, which releases Louise, and Slyphid saves them in time. Colbert has unloaded the cannon, which Saito examines using his Gandalfr powers, and quickly fires at the golem, but the round is stopped by Counter. Colbert, Kirche and Maricom unleash their most powerful spells, and manage to stop it's advance. Derflinger tells Saito that Dispell needs to be cast on the shells, and Louise refuses, saying she can't do it. Tabitha then kisses Saito, eliciting feelings of intense jealousy in Louise, causing her void powers to be activated again. Louise casts Dispel on the ammunition, which successfully pierces the Counter and destroys the golem. On the Ostland, Louise awakens to see Saito, and asks him if she's okay like this. Saito hugs her, and again declares his love for her, saying he does not love her just because he is Gandalfr. Then Louise kisses Saito while claiming that she has to because he's her familiar. Back in Tristan, Louise kneels before the queen, awaiting punishment for defying her. Henrietta punishes her by awarding her the royal mantle, declaring that Louise is now her sister and second successor to the throne, as well as returning Saito his Chevalier cloak. She then welcomes Tabitha as Princess Charlotte back to Tristan. The ending credits also show Maricom and Guiche wearing their mantles with their school uniforms, signifying that Henrietta has reinstated their noble status. When Louise tries to explode Saito when she sees Tabitha holding onto Saito, Sylphid grabs Saito and escapes with Tabitha.

After the discovery of a hot spring on their land, Saito decides it is the perfect time to have a hot springs party. Though he invited everyone, an unforeseen guest appears and shocks the crowd.