We saw the princesses enter the supposedly shielded Black Swan HQ all the way back in our 28th storyline, "This Mortal Coil," but I haven't actually gotten around to explaining why till now.
Also, that stuff Postuma's talking about at the end of her scene took place during our 36th storyline, "Chiaroscuro." What Coil's talking about, well, we'll all discover next!
Sixty-Seven - Adventures in Spider Sitting