Maybe because you were always perfect,and the polite child between your siblings,and you weren't causing any problems to him.

he didn't even thought that he will see you in that dress,at this hour, sneaking back to the manor.. He frowned as he crossed his arms looking at your guilty smile, rubbing the back of your head nervously.. He didn't expect that, especially from you.

"You're the last person I thought will sneak out the manor.." He said,his tone is kinda disappointed.