Sherry Henderson, code name Cirque, was a member of the Mystic Six, and wife of fellow member Charles Lodgeman.[1] She was an avatar of Aunghadhail, and looked like a slightly older version of Fey.[2][3][1]
She had bio-manipulation powers of some sort that allowed her to make attempts at duplicating Ultra-X-Amine, but she destabilized her powers due to self-testing with one of those attempts.[2]
Cirque died following the attack on a sorcerous cult that involved Rev. Englund and the current Whateley librarian, and possible relative, Miss Henderson. She lured the demon back to their base and banished it, dying in the action.