Of course you don't have a gender. "Gender identity" is a myth. Just go by your sex. It's what I do. I don't think there's anything "inherently male" about my identity, but my biology says I'm a guy, so, well, I'm a guy. It doesn't bother me. Why it bothers him (and yes, biologically, he is a he), well, creative types have always been a bit on the weird side.