Flat head man

The next day, Lingxia and her friends went to work as usual, but on the way to work, Lingxia always felt that someone was following her from behind, as if she was being stalked.
So he always looked back from time to time, but could not see anything.
His action made Bianca Joyce next to him a little confused, and she asked him what was going on, but Ling Xia didn't say anything.
It is enough for him to know these things. If Bianca Joyce was not here, he would turn around and catch that...