Sif Rembrandt is the first daughter of Patrick and Lisa Rembrandt, and a student of Rotsgard Academy.
She has a long hair and cute face.
He is his father, but she thinks he's a fool for his actions full of affection to his mother, sister and her. And, he is too overprotective when he don't want her to fight at Academy City Arena.
She loves her little sister and always takes care of her.
Because he saved her life including her little sister from deadly illness, she considered him as her saviour and good person. She ended up changing her perspective to appearance from outside to inside outlook of certain individual. She began to change her behavior and character and erased the existence of her past self.
In Academy Town, she always calls him Sensei when he become their mentor.
She has a romantic interest to Makoto. Furthermore, she will do everything she can to get his attention and become his wife. But, it is not easy to begin even Raidou is getting busy lately despite her mother agree about it.
"Right. It is assured that you won’t die, but if you didn’t have the resolve of betting your very self, you wouldn’t gone through the trouble of coming all the way here. There’s plenty of easier paths you could have taken after all. This is only a possibility, but there’s the chance that you can get close to Raidou-sensei and the Kuzunoha company, you know?” (Sif)