S1·E13 First Love? Beautiful Girl Lorelei!

In order to confirm the nature of the Gamia sisters, Tsubasa and Cross travel to Germany to meet a scientist named Heinrich Schtroheim. Back in Atami, Shiro falls in love with a mysterious young girl named Lorelei, who stops by the Kurogane house looking for Tsubasa who had already left. As the two begin to develop a strong friendship, Kouji learns the truth of Lorelei's background, only to find that she and Shiro have traveled to Germany in order to visit Lorelei's father. As Kouji and Ankokuji fly to Europe to follow them, they fall prey to a surprise attack by Dr. Hell's forces, while Shiro meets Lorelei's father: The monstrous Heinrich Schtroheim, who then, to Shiro's disbelief, introduces him to his real mother: Tsubasa.