Neugier: Umi to Kaze no Koudou

Duke, the son of Count Wein of Neugier, was exiled from the country by his father a long time ago. Traveling in faraway lands, Duke heard that his homeland was under attack. He decided to return to Neugier. On the way his ship was attacked by pirates, lead by a mysterious demon named Ord. After he barely escaped the ship, Duke found his way into his father's castle. He realized now that the pirates' attack and the monsters roaming the castle are connected. Although his father doesn't trust him, Duke is determined to save Neugier.