This is a term you'll see in Twitter and
Tumblr bios. Originally meant radically queer, but has since been co-opted by
people that support gross nasty shit
like zoophilia, pedophiles, and trans-race/trans-age.
*Not to be confused with Radically Inclusive or Radinclus, which means a user supports all queer labels, even the contradictory or ridiculous ones (xenogenders, otherkin, neopronouns, mspec lesbians), but not ones which are bigoted or cause harm to others. (Superstraight, "MAPs", trans-race, zoophiles, etc)