"I just hope these victims can move past this now," CNN quoted Maria Castro-Montes as saying Thursday.
Castro's victims -- Michelle Knight, Georgina DeJesus and Amanda Berry -- "wanted him to live out a life sentence, but really, was he suffering behind bars?" Castro-Montes said.
"I mean, getting meals, sleeping in a nice, warm, soft bed," she said. "You know, those girls didn't even have that luxury when they were being held captive in his home. They were being raped. They were being tortured. They were being beaten."
The three women, who were held captive in a Cleveland house for a decade, have not issued any statements since Castro, 52, was found hanging from a bed sheet in his prison cell Tuesday night. He was pronounced dead at a hospital.
Craig Weintraub, Castro's attorney, said while some will see his client's death as "a happy ending to this story," he cautioned "we're in a civilized society and no one should really be celebrating this."
While Castro, who was serving life without parole plus 1,000 years after pleading guilty in the case, was not under a suicide watch, Weintraub said corrections officials should have taken more precautions against a possible suicide.