OHSHC: Sister!

"Yayyy! I get to see my brothers" I thought. "So your the brother of -" The twins ask. "Sister" He corrects. "EHHHH!" They shout. "I'm Hajime -, sister of -" I said. Who is Hajime's brother? Anyway read to find out! First OHSHC fanfic so go easy. Suck at summaries but the story is better.