You're Mattheo's and Tom's Sister, also Voldemort's Kid.

Before a few days you got you Mark. Since then you have Problems to find Friends again in Hogwarts. Mattheo Has his mark already, so does Tom.

You were on your way to the slytherin common room. As you enter there sit: Tom, Mattheo, Theodore, Regulus, Lorenzo and Draco.

"Yea, um... And this is Our sister then..." Tom Said.