Schwan is thought as the sole inheritor of the throne. In his coming of age, he thought he'd be able to announce to everyone that he wanted to dismantle the ACCA however he wasn't able to say such.
Schwan is the son of the youngest princess of King Falke II. After the death of his aunt, the 2nd princess, Schwan was directly thought as the sole inheritor of the throne. When he saw Lotta during his coming of age, he ordered the investigation of her, then later finds out she was his cousin and immediately realize about Jean being a royal member of the family.