He was adopted by Michael Albus and he always calls Ariel Albus " little sister" and fight with her about the age.
He is actually Karl La Hire, who is the former Crown Prince of the Ballesteros Empire. His family was removed from power amidst the Revolution of the Wind while he was 9 years old. He is now living as a commoner with the family of Michael Albus.
He later expresses his feelings for Claire, just to realize she was the real identity of Nina Viento, who killed his parents.