Three_Emperors posted...

im asking why it would be offensive. unless the offense is at someone not using correct grammar the question stands

It's not "offensive" per se, but as we've covered multiple times in this topic, it's dehumanizing. You're free to use it like that, but people will develop an aversion to you, especially woman. Many people that regularly refer to women as "females" have a tendency to be misogynists that objectify women and see them as a prize. For that reason, they're justified in their aversion, even if you don't harbor those attitudes.