Fairy Tail: Princess of the Sea

Fairy Tail: Princess of the Sea (フェアリーテール：海のプリンセス Fearī Tēru: Umi no Purinsesu) is a special based off the series Fairy Adventure.

Description
Fairy Tail gets a request to apprehend Denney, a mad scientist who became a demon. However, after the mission is failed, a weak Kelpie is introduced to Fairy Tail and Luna and Nashi begin to have visions. After Fairy Tail is attacked and the Kelpie and Luna are captured, a man named Caspian steps in to help Fairy Tail save Luna and brings them to the dimension of Calder. With secrets of this dimension keeping everyone on edge, this is just another magical journey on the Fairy Adventure!

Summary
Nashi and Gary take a mission with Gale, Luna, Igneel, Luke and Mary Jane to a steampunk town Crowborough to apprehend Denney, a mad scientist who became a Mambu. During the fight, however, Denney seems to get away, but leaves a message: “The Moon has all the power my Master needs”. The mayor of the town only gives the team a proportion of the reward for their hard work in which they don’t accept the money as they did not finish the job.

Meanwhile, Lance and Aine decide to have a date on the beach. As they take a stroll, they spot an injured Kelpie laying half in the water and half in the sand. Aine and Lance help it, but once they notice it is unconscious, they decide to take it back to their apartment so Aine can heal it.

The team comes back to Fairy Tail without of reward money, but the parents cheer them up, nearly getting in a fight in the process. Nashi decides to head home early and goes to her thinking place, which is a pond in the center of the woods. Nashi begins to have a vision of the Temple and swims with a mysterious light with a voice (Princess Nanami). Luna saves Nashi from accidentally drowning. The Dragneels have dinner when Luke brings up the Kelpie at the guild, which peaks Nashi's interest. Later that night, Nashi shares a dream with Luna of the Temple and the war, and both decide to go to Luke, who tells them about the dimension of Calder.

Later, Nashi takes a trip to Lance and Aine’s apartment. Nashi encounters the Kelpie. Once Aine completely heals the Kelpie, Aine invites Nashi to accompany her as she takes the Kelpie to the beach. Nashi watches the Kelpie as Aine gets food until the Kelpie leads her into the water and shows her another vision of the Sea Jewel and the Temple. Nashi remains confused, but keeps it to herself once Aine returns.

Natsu, Lucy, Gray, Erza, and Juvia are called away on a mission while the Master left on guild duties, leaving Macao in charge. Nashi eats dinner at the guild with Gary, Cane, Penelope, Silver, and Paige, but ensures to check on her siblings. Disturbed by her visions, Nashi doesn’t realize she has eaten little until Gary fusses over her. Denney and other familiars shortly attack the guildhall and make a claim they need the Sea Jewel. Fairy Tail fights back only for Denney to kidnap Luna and the Kelpie.

Gary comforts Nashi as she and her brothers try to plan how they will get back Luna. Nashi is called out to the pond where a Kelpie emerges and transforms into a human teenager by the name of Caspian, knight of the Temple and protect of Princess Nanami. Caspian is brought to Fairy Tail and explains he knows where they can find Luna. Macao decides to send out a rescue mission with Mystogan, Nashi, Gary, Gale, Luke, Igneel and Mary Jane to go with Caspian and bring back Luna.

Caspian leads the group to a secret train that goes into between dimensions. Caspian explains about the Temple on the train ride there and tells them about Denney and the familiars they saw. Nashi falls asleep with Gary and has a dream about the Temple and the mysterious telling her about the power of love. Nashi wakes up to find Caspian staring at her, but dismisses it. Gale has a dream in which Luna is growing farther and farther away from him due to her captors. A voice promises Gale he will be able to protect Luna if he obeys. Gale agrees and disappears from the train.

The Fairy Tail Mages and Caspian arrive in Calder and make arrangements at Hayes Hotel. Caspian decides to give the Fairy Tail Mages a grand tour of the kingdom. Gary decides to explore by himself, jealous of Nashi taking a liking to Caspian, and discovers an old man whom warns him about the kingdom. Later that night, a suspicious Gary sneaks into Nashi’s room while Mary Jane is still out and recalls the warning he receives, but Nashi misinterprets his concern as him wanting to leave Luna and kicks him out of her room. Caspian offers Gary a train ticket home, but Gary decides to walk off his frustration, leading him to be kidnapped.

Gary wakes up to Luna healing him and finds that they are both in a dungeon cell with the Kelpie and the real Caspian whom explains his imprisonment and the Caspian on the surface to be Demon Alva who plans to use the Sea Jewel to rule Calder.

While the others of the team explore more, Caspian decides to take Nashi on another personal tour of the kingdom. The two go to dinner together where Caspian attempts to take advantage of Nashi. Luckily, Luke and Igneel get in the way. Mystogan handles battling Caspian with Luke and Igneel while Mary Jane helps Nashi get away. However, the team is put under a sleep spell while Mystogan is punched unconscious due to his resilience of Sleep Magic and the team is captured.

Nashi wakes up to Luna healing the others. The team is grateful to see her and Gary in good health and the two explain about the real Caspian and Demon Alva. A familiar and Gale come to take Luna away, much to Nashi’s distress. A screen is projected onto one of the dungeon walls were they see Luna chained to a wall and Demon Alva touching her inappropriately. He begins to drain away Luna’s magic, making Nashi, Luke, and Igneel cry out to Luna. Soon, Luna is left on the brink of death as she has lost so much magic. Demon Alva grows powerful and calls upon his familiars and they begin terrorizing Calder. Nashi weeps for her sister and whispers, “I love you, Luna” which causes the jewel on the Kelpie’s head to glow. Gale frees the team, telling him of his plan he made with Luna and his contact with the familiars. Gale leads them to Luna whom is barely breathing. A human Princess Nanami and revitalized Caspian enter the room to explain to bring Luna back to life a being stronger than the demon must defeat Demon Alva.

The team (minus Gale and Luna) and Caspian and Princess Nanami begin their battles with the familiars. Nashi uses her ultimate form of Divine Soul: Goddess with the help of Princess Nanami. She uses her God’s Arrow to finish Demon Alva and reduce him to a Nazaris. The familiars ultimately disappear back to their own dimension. Luna gains her magic back, much to everyone’s joy. The Temple returns to its rightful place and Calder returns to its natural state. Princess Nanami and Knight Caspian help the team find their way back to the train station. Princess Nanami thanks Fairy Tail for their help and promises Nashi she shall grow strong and prophesies Luna will be the key to something big in the future. As the train leaves, the Fairy Tail members wave good-bye as Princess Nanami and Knight Caspian do the same, hand-in-hand.

The story ends with the Fairy Tail team enjoying their time on the train. Igneel is telling a story with Mystogan adding comments and Nashi and him bickering only to have their respective partners hold them back from fighting. They arrive home and walk back to the guild—which is being rebuilt. Their parents are home and inquire of the happenings of Fairy Tail in which each member laughs, even Luke.

Back in Calder, Princess Nanami and Knight Caspian are riding Kelpies on the beach when they dismount and Caspian proposes, in which the Princess is ecstatic and leaps into his arms.

Back in Magnolia, Gale comes over to take Luna out on a date. Igneel and Luke give him a hard time, but Luna scolds her brothers and goes on her date. Lance and Aine have another beach date. Mystogan and Luke are at the guild discussing books with Ena following them, in awe. Igneel and Mary Jane are bickering in an ice cream parlor. Cane and Paige are arguing while Silver laughs and Penelope holds back Cane. As each seen is traveling by, a white light is seen floating around.

Gale and Luna are on their picnic date, Luna laughing at Gale. She sees the floating white light and she smiles. Gale is confused, but Luna holds his hand, sending him into a blush, but they hold hands tighter and lean on each other as the light hovers above them, leaving the story to end.