Feminist: Because she's a woman, and she's on Tumblr.
Someone needs to sig this.
The label 'feminist' does not describe very much. I could mean people who are fighting for women to be equal to men (despite the fact that they basically already are), people who think that women are better than men, or people who think that women and men should be segregated.
It describes a specific intellectual and political movement. There's a reason people can say things like "second wave feminism". There is a history behind the thing, it isn't just a label people have arbitrarily given themselves as you seem to be implying. It may be that for Tumblr crazies (I don't have a Tumblr account, so I wouldn't know) but they don't speak for feminists as a whole. Personally I think this author's
blog post explains it better than I can.
Look at all those labels. S: Cisgendered? Demiplatonic? Aromantic? Panwhut? >_>
The 'about' is 75% labels...
Also, the phrase 'check your privilege' says nothing and a lot o things at once. S: It apparently originated from a nice intellectual essay some years ago, but eh.
While I can't speak to the first two, Aromantic and Pansexual are legitimate and useful labels.
Aromantic is to romance what asexual is to sex. Its generally considered a subcategory of asexual, but since aromantics can still want sex they obviously aren't going to describe themselves as asexual because that's a very good way not to get laid.
Pansexual is an orientation in the same sense that bisexual is, except that pansexuals are attracted to people of ambiguous gender. So a bisexual would be attracted to men and women but not the androgenous or ambigious. Whereas pansexuals could go for any of those categories.
Just because some people abuse a word doesn't mean that word has no meaning