It is rare that this happens to you, it will be because they see you in a masculine way, but more effeminate and they believe that you are gay, you give them tenderness? I don't know lmao.
In my case, some girls are bitches with me and they look at me with envious faces, and I step over them ignoring them, the girls usually look me up and down when they feel inferior to me, and I just laugh at how ridiculous some of them are, usually it always happens to me in the school.
its like a rivalry between womens, and most are fat, and I'm thin, so perhaps that's why some look at me with envy, who knows xD