Sinku Izumi, a young extreme traveler, managed to visit the magical world of Froniard during spring break. Under a raspberry‑colored sky with flying islands, an adventurous spirit prevails; wars resemble cheerful sporting games, and local beauties all seem perfectly matched with ears and tails! A resident of our world was hailed as a hero – and he became one, resolving in a short time the sudden flare of hostility between neighboring countries Galett and Biscotti, as well as taming an evil demon. No wonder the boy made many friends, and even more girlfriends. To his dearest of them, Princess Melchiore Filiano Biscotti, Sinku promised to return – and heroes always keep their word! Company is more fun abroad, so during summer vacation a whole delegation goes to Froniard. Sinku invited his childhood friend Beki and cousin Nanami – an old rival and equally determined athlete. Now Biscotti and Galett have their own heroes, and the modest Beki too; we believe she will not stay on the sidelines. So, troops are gathering, sacred weapons await, new warriors, knights and crowned individuals rush onto the stage. The days of Sirius"s "dog star," the hottest summer days in the world of the series, are still ahead!