about butch and femme, i cannnot understand?

I can never understand a butch and femme relationship.

Butches say they are feminists, but some of them still enjoy fxxking their girlfriends with strap-on dxxks. They can be even more dominant than men during sex.
I have read some stories written by butches, and many of them contained phrases that seem to insult women like "sxxk my dxxk, girl", "you are my cute little slave and i'm your big daddy", "i took possession of her" etc.

I mean WTF? Feminists should protest against such insulting stuff. But instead they are using them.
It is like the butches are simply taking over the traditional role of men while at the same time accuse men of being "dominant".