Saito is on Louise's bed with Siesta and he starts making perveted comments in his sleep when Louise wakes up and explores the door and Tabitha appears to "protect him" then Mr.Colbert takes them to Romalia to see the queen Henrietta and the king appears and he invited them a feast, Louise gets mad with Saito and he walk out to Siesta room and Siesta talked how she fights like love rival's and then he went to find Louise when he heard her screaming. After Tiffania asked Colbert-sensei to teach her how to summon a Familiar. Saito ran and he fought 2 people that were thieves and Tiffania is learning how to summon a familiar when Saito is fighting he falls and comes through Tiffania's Familiar "portal" nothing really happened, and then they got back and Saito kissed Louise and then Tiffania comes in and Louise started to say that Saito forced her.

Louise and Saito enjoy some time alone as they explore the city of Aquileia. Henrietta asks Vittorio to keep Louise and Tifa safe but despite both his and Julio’s assurances Agnes and Henrietta still suspect trouble. Tifa wonders if she really did summon Saito and notes that now seeing him makes her feel flustered. Louise shows off her priestess outfit to Saito and they begin to get intimate but Malicorne ruins their moment. In Galia, Bidalsha creates fire stones for Joseph who reveals he will use them as weapons while Sheffield confirms that she will enact her plan tomorrow. The next day, Tifa tries to confirm if Saito is her familiar by kissing him, but the two are interrupted by Malicorne and Montmorency. Louise is taken aside by a peasant girl and when Saito goes to look for her he is ambushed by Bleu. The peasant girl reveals herself as Janette, Bleu’s sister, and subdues Louise and hands her over to Sheffield. Janette retrieves Bleu and informs Saito of Louise’s kidnapping, so he frantically searches for her to no avail. Saito and the others regroup and Tabitha reveals the kidnappers are from Galia, meaning Joseph is behind the kidnapping. Before they can act, they are informed that Galia’s airships are heading towards Romalia. Onboard one of the ships, Joseph introduces himself to Louise and tells her he will use her as part of his plan.

Sheffield uses the stolen mirror artifact to transfer Louise's Explosion power to Joseph and he uses it to detonate a fire stone, destroying the airships attacking him. Saito and Tabitha make their way towards Joseph’s ship while he detonates another stone on the retreating ships. Louise manages to escape and takes the last stone with her, but Sheffield’s gargoyle recovers it, as Saito and Tabitha arrive to save Louise. Tabitha and Louise go after the gargoyle, while Saito uses Julio's gift, a modern gun, to incapacitate Sheffield and confront Joseph. On the ground, Tifa uses ancient magic to stop the gargoyle, allowing Tabitha to recover the stone. Joseph uses his void power, Acceleration, to move at high speed and subdue Saito, but Louise and Tabitha return and save him. Tabitha fatally wounds her uncle, but decides against killing him just as Sheffield returns and forces the group to leave her to die with Joseph, so the trio escapes just as the ship explodes from the last stone. Back at the Cathedral, Saito voices his suspicions that Vittorio used Louise as bait to lure Joseph and kill him, to which Vittorio admits. Louise tells Saito that it’s alright since she has him to protect her and he agrees, reaffirming their bond. Tifa, who was watching, both admires and is saddened by their close bond, believing it proves that Saito is not her familiar.

At the Magic Academy, a ball is held in celebration of Louise, Saito, and the others deeds in Romalia. Louise and Saito dance, and he expresses his wish to be with her forever, leading to a passionate kiss between the two. Meanwhile in Galia Tabitha uses an antidote given to her by Bidalsha to cure her mother. The following day, Siesta overhears how Tifa tried to kiss Saito and suggests to Louise that they should separate Saito from Tifa by buying a house were only he and Louise would live, and Louise agrees. Louise rejects all of Saito and Siesta’s choices, and becomes further irritated when Siesta reveals she too will be living with them. Things become worse for the girls when they discover Saito has become increasingly popular with women due to his heroic status, and so decide to hasten their efforts. Back in Galia, Tabitha is asked by her mother to become the new queen for both the country and her father’s sake. Three days later, Agnes brings Saito and Louise to Henrietta, who informs them that Tabitha will be Galia’s new queen and to reward Saito for his previous deeds with a portion of her territory. Saito, Louise, and Siesta arrive in their new land, Ornières, only to find that it is a forest and their mansion is old and decrepit, but stay anyway since it was a gift. That night, the trio is visited by Tabitha who reveals she will be moving in with them since she postponed her coronation.

At Ornières, Tabitha still hasn't decided if she wishes to be queen of Galia yet, since she has to be married and have a baby before she becomes queen. Louise and Saito spend time with each other on a hill and they share a kiss. Eleanor soon comes over and tells Louise that she can't live with a commoner like Saito and demands her to return home. Louise then convinces her sister to let her stay by promising to have Saito act like a noble. Louise starts training Saito for the whole day and the two inevitably argue, leaving Saito sleeping on a busted lounge chair in the basement. Later that night, as Louise is worried in bed, Saito discovers a hidden passage that leads to a secret room with a mystical mirror. He touches the mirror and discovers that it's portal that leads to Henrietta's mirror. Henrietta goes through the mirror and meets with Saito. As Louise explores the mansion to search for Saito, she finds Saito in the room where she sees him and Henrietta kissing. Her tears fall as she quietly leaves the passage unnoticed. Saito tells Henrietta that he truly loves Louise and cannot accept Henrietta's feelings. Saito soon leaves to hear Del tell him that Louise was here, crying, and Saito ran off to find Louise leaving on a horse. Louise just smiled and apologized for not realizing his feelings towards the princess. At the Magic Academy, Tabitha then told Louise that she would have Saito as her husband. Kirche explained to Louise that queens (i.e. nobility) can't freely fall in love since they are often betrothed so she must honest with Saito and tells her true feelings as to not put him in a struggle. Saito is afterward seen on the hill again, thinking about going back to his world since Louise is not there with him. Louise comes back to Saito where and confesses that she wants to be with him. Saito happily tells Louise that she is the one who he is in love with and they lovingly embrace each other.

A hot spring is uncovered at Ornières, so Saito decides to modify it into a bath and invites everyone he knows to try it. Louise later thanks Tabitha for helping her make up with Saito, but Tabitha warns her that she meant every word and next time she will take Saito for herself. That night, Slyphid reminds Tabitha that she is running out of time with her decision, so Tabitha chooses to make her move on Saito. Her attempt is quickly stopped by Louise. The following morning, everyone arrives where they are greeted with everyone else invited. Upon everyone else's arrival, Siesta and Louise soon spot a hooded figure entering the mansion. Louise and Siesta capture the figure, who turns out to be Henrietta, who explains she wanted to try the hot spring. As Henrietta and Louise bathe, Louise confronts Henrietta on her feelings towards Saito, which soon turns into a cat fight since Henrietta confessed that she loves Saito. They soon make up, although Henrietta tells Louise she will still pursue Saito. Later, Saito talks with Henrietta to assure his feelings for Louise clear, but Henrietta reassures him that she has not given up on him. The girls then enjoy a group bath but Tifa soon becomes light headed from soaking too long, so she stays in for the night as everyone else leaves. With everyone gone, Louise and Saito bathe together in the hot spring and promise each other they will be together even in death, and passionately kiss. The two soon return to their room where they passionately kiss once more. As Louise is lied down, she signs at Saito that she wants to have sex. But as Louise discovers Tiffa asleep in their room, Louise misunderstood her presence and blows Saito up in anger about breaking his promise not to cheat on her.

The Gensou Siblings (Jack, Bleu, and Janette) attack Ornières to kill Saito, so a battle between them and Saito and co. breaks out. As the battle goes on, a trio of elves sneaks in to capture Tifa, but Saito confronts them. The fourth sibling, Damian, appears and uses alchemy to cease the fighting, and one of the elves uses that magic with his own to capture both Tifa and Saito. The two awaken in a desert oasis and meet their captor, a female elf named Luctiana. At Tristain, Henrietta tells Louise they cannot send a rescue party since Romalia is handling the situation, but Louise resolves to save Saito anyway. Luctiana tells Saito and Tifa she is holding them to study human culture, and also reveals the reason why they were kidnapped was because Tifa is a void mage, a power which elves fear, and because Saito is Gandlafr. As Louise prepares to leave she is joined by Siesta and Tabitha, who are then joined by the rest of their friends on the Ostland. Saito and Tifa try to escape, but are unable to since a magic binds them to the area. Saito assure Tifa that they will escape, and the two decide to go for a swim in the oasis, where Saito discovers a submerged fighter jet.

As the Ostland flies at max power to the elven land, Saito and Tiffa are put before the council to decide their fate. Eshmael provoking words causes Saito to lash out, causing the other council members to agree that the barbarians must be destroyed. Will the Ostland make it in time or will a war start with the elves?

The Ostland makes it to Reynald, Gallia’s Kingdom, where Tabitha has offered to repair the ship. While there she informs them that she is taking the crown and becoming Queen. Louise has the deal with her jealous feelings as Saito spends more time with Tiffa.

Saito, Louise, and Tiffania have been summoned to Romalia by his Holiness. They were to meet Julio near the Aquaria’s border, but once there they witness a scene that will affect everyone’s future.

Julio and Saito continue their battle with the Ancient Dragon, but Saito won’t talk about the loss of his partner. Louise can see the pain on his face and has faced with her toughest decision to date.

The students of the Magic Academy set a barrier to hold off the Ancient Dragon and its minions while waiting for reinforcements. Meanwhile Saito returns home, but instead of getting in, he decides to find a way to get back to Hakelginia and help Louise and the others instead, and has an idea upon looking on a newspaper. Despite the combined efforts of the students and the forces of Tristain, Gallia, Romaila and an Elven fleet led by Vitartial, the dragons break into the academy and Louise decides to escape with Tiffania on Sylphid to protect the others, as the Ancient Dragon's target is only the two of them. Back on Earth, Saito manages to hijack a Mitsubishi F-2A Jet Fighter and makes it through a solar eclipse to return to Hakelginia and help the others just when Louise was about to be eaten by the dragon. Derflinger appears before Saito, much to his surprise and it is revealed that Derf was actually still alive inside Saito's Gandalfr rune. Saito fires all of the Fighter's missiles into the Ancient Dragon, but it only weakens its defenses. Louise contacts Saito through the world door and he pulls her through it into the cockpit to have her cast the Explosion spell combined with Lifdrasir's power on the dragon, but she refuses out of fear for his safety. Saito tells her he will not die no matter what and reassures Louise with a kiss, finally convincing her. After closing in on the dragon, Saito and Louise eject from the jet as it crashes into the dragon, further weakening it, and then Louise casts the enhanced Explosion spell and the Ancient Dragon is finally destroyed. Saito and Louise land safely but she gets desperate wondering if his life was estinguished by Lifdrasir's side effect but it is reveled that despite Lifdrasir's power was exhausted, Saito's other rune kept him alive. They are soon joined by all their friends, which prompts Saito to propose to Louise, which she happily accepts. Some time later, Saito and Louise get married and they make use of the 'World door' to pay a visit to Japan for Saito to introduce Louise to his family.