If I remember correctly, at first it was suggested or tagged that way from just assumptions, then it was removed considering the original website didn't have such tag, also a veeeeery similar work that was actually yuri came out close to the same time creating more false assumptions.
Then later on, people were saying that it should have the tag because of Asa's friend and there was discussion about it but ultimately, I don't think it should have tags for all the people involved in this story because is about Asa and Makio and everyone else is living their own life.