Tangled Webs (The Black Jewels 6)

The invitation was signed Jaenelle Angelline, she who had been both Witch and Queen...
 
Surreal SaDiablo, the former courtesan and assassin, is the first to arrive—only to find herself trapped in a nightmare created by the tangled webs of Black Widow witches. And if she uses Craft to defend herself, she risks being sealed in the house forever.
  
Now, Jaenelle and her family must rescue Surreal and the others inside without becoming trapped themselves—and uncover the monsters capable of designing such an evil place...