vriska's pool of blood at her death forms the silhouette of callie ohpeee's horns
at first i thought it might be more likely those are Makara horns, given the ancestral feud in play between the Pyrope, Serket and Makara bloodlines, but I think this could be read as a symbol of Vriska’s Martyrdom.
Scorpio is the sign of the Conqueror, which is the path given to Caliborn by Yaldabaoth; the other path, leading to death, is the path of the Martyr, given to Calliope. as such, the version of Vriska who dies rather than lives on to become the Conqueror could be seen as taking on an aspect of Calliope.