I Googled her and lo, BtVS connection.
http://en.wikipedia.org/wiki/Potential_Slayers
Caridad - A girl from the Philippines to whom Xander is attracted; first seen in "Dirty Girls". She too survives the climatic Hellmouth battle according to the Buffy magazine. Caridad is portrayed by Dania Ramirez.
http://en.wikipedia.org/wiki/Callisto_(comics)
Dania Ramirez portrays her in the third X-Men movie. She is a member of Magneto's Brotherhood of Evil Mutants. In place of an eye-patch and physical disfigurement, this version of Callisto is beautiful, yet heavily tattooed. Her powers have also been altered to move at incredible speeds and the ability to "sense" other mutants around her, and assess their abilities and power level.
P.S. X-Men has Reavers?