Allison & Lillia

The story is set in a world with a continent split down the middle by a mountain range and a vast river. The eastern side is known as Roxche, and the western side is Sou Beil. The two sides have been at war for the past 130 years, though an armistice has been in effect for the past ten years. Wil, a young man from Roxche who enjoys reading books and has a photographic memory, is spending a leisurely summer vacation at his school's dormitory when his old friend Allison, a young girl his age who is now an Air Force pilot, arrives in a biplane to greet him after not seeing him for six months. The two take a drive together on Wil's motorcycle from school and run across an old man waiting on a bridge who is well-known in the area for telling false stories. They give him a ride to his home, and while there he tells them a story he claims to be true: that there is a treasure in the western region Sou Beil which could end the conflict between the warring regions. Before he can tell them more, a man who claims to be from the town hall takes the old man away, though Wil quickly notices that the man was most likely lying. Allison and Wil chase after them and find that the old man was taken away in a large plane. Allison and Wil steal a plane in order to find out where the old man was taken.

While chasing the plane, Allison and Wil get attacked by a fighter plane and while getting away got tangled on some power lines, ultimately causing their plane to crash. As the sun is rising, Allison sees a fawn and approaches it, only to anger the fawn's mother which goes to attack Allison, but Wil gets in the way as the deer hooves his head, making him pass out. Allison carries him most of the rest of the day until they find a cottage with a single old woman who treats Wil injuries and listens to Allison's reasons for coming over to the western region. Via Allison's and Wil's sleep talking, the woman discovers that they knew and grew up with an old woman named Moot who had defected to Roxche to run an orphanage; she was known henceforth as a traitor in Sou Beil. After hearing the hardships they have been through, the woman's opinion of them and people in general from Roxche changes. She gives them her now-dead husband's and son's military uniforms to aide in their rescue of the abducted old man.

Allison and Wil successfully infiltrate the military base where the old man is being held, and manage to help him escape by giving him a hair pin for him to pick the lock on his jail cell. While getting away, Allison and Wil meet the lieutenant who Allison met six months previously who took interest in her. Allison and Wil manage to steal a sea plane while the old man holds back the enemy, but the old man causes an explosion right after the plane takes off, and is shot moments later. The lieutenant, Ker, is given the order to follow Allison and Wil and kill them if they attempt to cross the border; as a precautionary measure, another will follow to make sure Ker does not hesitate to follow his orders.

After Ker catches up to Allison and Wil, a dogfight ensues which ends with Allison shooting Ker with paintballs. Two other fighter planes catch up and try to shoot down both Allison and Ker, but Ker gets the better of them, shooting them down instead. Allison, Wil, and Ker make it to the cave where the treasure is and find it to be an ancient mural showing Roxche and Sou Beil sharing fire, signifying at one time the two cultures were at peace. Two officers from the Sou Beil army arrive and almost shoot Allison, Ker, and Wil, but Wil shoots first. This causes one of the officers to misfire on the cave roof, causing a cave in, killing both officers. The mural serves to end the war between Roxche and Sou Beil.

Wil goes on a field trip with his school to the Kingdom of Ikstova where he meets up with Allison due to help from her friends in the Roxche Air Force. Allison and Wil go to a Sou Beil military camp where they meet up with Ker, now a major, and he invites them to have dinner that night. Allison and Wil get caught in a blizzard and end up in a town hidden deep in the forest where the villagers are suspicious of them. The villagers drug Allison and Wil via the tea they drink which knocks them out. When Allison and Wil do not show up for dinner, Ker goes to look for them and meets a girl named Fiona from the village.

Allison and Wil escape and meet up with Ker in the village where they run into Fiona who takes them back to her house. She tells them that if they take her to the capital city Kunst, she will not turn them in to the villagers. She wants to go interrupt a political speech in order to inform people that she is the princess of the royal family of Ikstova who were thought to have been all killed ten years prior, but she survived and went into exile; Fiona's real name is Francesca. They try to escape the village but are easily surrounded by the villagers, but after hearing of Fiona's plans, the village leader lets her do as she wishes. Fiona, Ker, Allison, and Wil head towards Kunst in Ker's vehicle.

Allison, Wil, Ker, and Fiona make it back to the Sou Beil air base where Ker and Allison concoct a plan to allow Allison and Wil to steal a fighter plane while Ker and Fiona fly a commercial sight-seeing plane. In the midst of the plan, the soldiers block the runway, which causes Allison to head toward the nearby town, and eventually manages to take flight as she is descending into the nearby cliffs. On the way, Fiona tells Ker that she is not a real princess, and he in turn tells her that he is not a real hero, as it was mainly due to Allison and Wil that the mural that ended the war was discovered. Ker makes a grand entrance by landing the plane as the crowd gathered for the political speech get out of the way. Ker introduces Fiona as the thought to be dead princess Francesca, but the politician Nihito objects.

Nihito asks Fiona to show proof of her claim, and she produces a royal medallion which is confirmed to be real by one of the guards who was at the palace when it burned down years ago. Fiona goes on to accuse Nihito as having a part in her family's death due to a small cuff link of Nihito's that she had in her possession. Nihito retaliates by taking Fiona hostage and running up to the tower when Ker confronts him, and nearly loses his life. Allison and Wil fly their plane close to the tower which creates a strong wind that blows Nihito off the balcony which kills him. Later, Wil figures out that Fiona is not actually Francesca, and Fiona goes on to tell how she met Francesca the night of the fire, but only learned much later that she was her older twin sister.

During spring break from school, Wil meets Allison and Fiona on a luxury train which runs between the eastern and western countries. Halfway over the Lutoni River, the train stops for a flower tribute in observance of the war victims, and Wil tells Fiona how Allison's father was killed by his own subordinate since it would have been dangerous having him caught as a prisoner of war due to him likely being in the intelligence division of the military. The train makes another stop on Green Island and picks up Ker who is in disguise, and a Major with the Sou Beil military on assignment.