I am currently attending college, and I can confirm that many at my age refer to a good girl friend as a "bro". It may be stupid and immature, but it is what it

I am currently attending college, and I can confirm that many at my age refer to a good girl friend as a "bro". It may be stupid and immature, but it is what it is. As other commenters has said, "bro" is describing the relationship and not necessarily referring to any specific gender.