The Union Festival comes to a close, and Millihi and Sink take some time to relax at Yukikaze's house. But things take an unexpected turn when Millihi finds a strange crystal, and the three are engulfed in a blue fog...

Wanting to get a gift for Rebecca, Couverte along with Rico and Noir descend into the vault underneath Castle Eschenbach. All the traps should be disabled in this ancient maze, right?

The Heroes Return home and reminisce.

The three heroes return to Flonyard but Shinku and Nanami's summoning is disrupted by a lighting bolt, leaving them stranded in a forest. While their friends search for the duo, they meet a girl named Sharu who offers them aid.

Cinque and Nanami help Sharu protect the forest against hordes of rogue beasts, but after reuniting with their friends, a bigger threat appears.

The armies of Biscotti, Gallete and Pastillage join forces to vanquish a powerful demon that threatens the forest. To help Sharu seal the demon, Cinque, Nanami and Rebecca bring their powers to the limit.

Cinque and Rebecca joins a scientific expedition that turns into a dangerous adventure when a cursed creature threatens the local Fairies.

After almost defeating Leonmitchelle in the challenge, Prince Leaf from the Kingdom of Halver is showed around Galette, Biscotti and Pastillage by the locals, and after attending one of Milhiore's concerts, they gather around Adel, who is about to tell them old stories of the past.

Adel and Valério tell Couvert and her friends their exploits to clear the land of demons along with Brioche, Isuca and Valério's long lost sister, Princess Clarifier, the one who summoned Adel to Flonyard and became her closest friend.

Upon learning that something is amiss with the Sky Priestess, Sharu seeks for the Heroes' aid and departs with them to the insides of the Star Whale, a massive flying deity where she resides.

Upon meeting the Sky Priestess, Cinque's party learns that the Star Whale is infested of demons, and the only way to cleanse it is by the voice of a talented singer. With Aria, the Sky People's songstress unable to sing, Cinque and Rebecca return to the surface seeking Milhiore's aid, but a strange enemy appears, intending to claim Aria for himself.

Once returning with reinforcements, Shinku joins forces with Gaul against Verde to rescue Aria, while Milhiore uses her song to heal the Sky Whale.

Once the Sky Whale is restored, Shinku and his friends return to the surface. Sometime later, the heroes are once again sent back to Earth, promising to return to Flonyard in the near future.

One on one battles continue with Becky vs. Millihiore, Rebecca vs. Hina, and Sink vs. Gaul. A wild card appears to shake the battle up even more.

With the crisis averted, the heroes return to their respective kingdoms, but when Nanami and the Genoise Trio pay a visit to Pastillage, they get into a slimy mess when some dangerous creatures break free at the castle.

The time has come for Leonmitchelle's annual challenge in which whoever defeats the princess earns the right to marry her, but this time, a new and powerful contestant who is an old friend of hers, appears as well.

Couverte and Sink have accidently released the Demon King from his sleep. Even with all the heroes powers combined he proves to be a formidable enemy. Only the Hero King can stop his rampage.

Biscotti's army fights a losing battle with the forces of Galette until Cinque manages to hold off the enemy's offensive fighting alongside Captain Éclair Martinozzi. However, the two must join forces to confront Galette's commander and most powerful warrior, Leonmichelli Galette des Rois.

The battle ends with Biscotti's victory, but Cinque learns that Millhiore was not aware that once he was summoned to Flonyard, he cannot return home. Meanwhile, Leonmichelli's younger brother, Gaul, learns of his sister's defeat and is eager to face Cinque in combat.

Cinque Izumi makes a promise with his best friend Rebecca to go flower viewing during the last three days of Spring Break. However, while he is alone trying out some acrobatic moves in school, a dog appears and opens a magical portal while Cinque is in mid-air, resulting in him jumping through the portal with the dog. He arrives in the land of Flonyard, and is greeted by a beautiful girl, albeit with bestial features like dog ears and tail. The girl, who introduces herself as Princess Millhiore, requests for his assistance, which he agrees to and becomes the Princess' Hero, in order to drive away the forces of Galette which seeks to invade Biscotti.

Gaul's special forces, the Génoise trio, kidnaps Millhiore and he challenges Cinque to a duel. Cinque, Éclair and chief researcher Ricotta Elmar come with a plan to storm the fortress where she is being held to rescue her in time for her victory concert. Heavily outnumbered by the enemy, Cinque and Éclair manage to turn the tides when the freelance knights Brioche d'Arquien and Yukikaze Panettone come to assist them.

Cinque and Gaul's duel is interrupted by Leonmichelli who reprimands both for ruining Biscotti's victory party. Almost running out of time for Millhiore's concert, Cinque comes with a plan to return the princess to the castle for her performance.

At last Ricotta and her assistants come with a way for Cinque to return home. However, she finds that by doing so, not only he will forget all memories and experiences of his time at Flonyard, but he will never be able to come back. Upon learning of it, Cinque asks Ricotta to not tell the truth to the others, as he does not want them to send him off with a sad face.

The monster grabs Millhiore and flees the fortress on a rampage. Cinque struggles to reach the princess before she is absorbed by the creature, while she learns that the monster is actually a fox deity cub whose body was pierced by a cursed sword.

Cinque learns from Millhiore how she used her stargazing powers to learn about him and why she chose him as her hero. Meanwhile, Leonmichelli confirms by using her own stargazing powers that an ominous fate awaits them.