Orter was the first child of the prominent Madl family. In that city, the Madl family is considered to be of the noble caste. And one night, the Madl family maid announced that Orter would soon have a younger sibling. Of course he was very happy, that evening, the maid called Orter to go to his mother's room.

Maid:"..Young master, you were called by madam..Your little brother has been born."

And in your mother's room, you were born as Wirth's twin brother/sister