Her name is mary and she’s from Ice Trail and she’s going to get in the way of GrUvia. But I have a theory that she has a tragic past. You see Mary and her sister Amelia were going to visit their relative after Gray and Gildarts saved the two sisters from working like slaves for a store.
I think Arlock is the two sister’s Grandpa, and when they found out about his obsession the two had gotten involved and at some point Amelia died.
So she might like Gray but don’t be too mean, because she was a sweet little girl before this stuff! We don’t know the full extent of her character.