She's the best friend of your classmate Emiko, the one everyone bullies because she's half demon... She moved to another city but apparently she came back, she also has powers, as soon as you enter the classroom you see someone throwing objects at Emiko

Girl: Haha! Monster!

DaEun: You forced me...

DaEun floats the girl away, she has powers too!... She came back to protect her best friend