Some girls are naturally shy. When they meet a boy they like, they will avoid it at a distance. They are afraid of making eye contact with each other, but they enjoy secretly staring at each other behind their backs. Generally, such boys are excellent and inviolable in the eyes of girls and belong to the category of male gods.
In addition, some girls are afraid of boys. It is possible that this boy did something that made the girl feel psychological shadow and scared, such as sexual harassment and so on.