I wish there were another catch-all word like "feminist" that I could use to express my belief that all people -- male, female, transgender and otherwise -- should have the exact same fundamental rights and opportunities in this world we share. "Gender-equalist," perhaps? "Advocate for gender fairness"?
One origin story for f*ck is that it comes from when sex was outlawed unless it was permitted explicitly by the king, so people who were legally banging had Fornication Under Consent of the King on their doors, or: F.U.C.K. But obviously that's wrong. And if you do believe that, stop it. Stop it right now.