Though I hate that Dahlia was evil and cruel and committed numerous crimes, I too feel bad for the abuse she suffered as a child. Her mother forced her into spiritual training against her will and THEN her father in my opinion likely abused her physically, verbally and sexually. Abuse from her dad is probably what made her into the murderess everyone hates.
Like many of her fans, I too wish that there was some way her soul could be saved and she could find redemption. I often wonder who she could've become had it not been for the abuse she suffered as a child. She probably would've in my mind become a good hearted Tsundere and used her charm and cunning to help people.
This comment is old but I dunno - the Hell that Dahlia ends up stuck in by the end is one of self-loathing and of having lived a life of pitiful failure and misery with nothing to show for all her hatefulness and crimes against others she felt had crossed her even after her own expiration. I actually like the idea of Dahlia, from within that self imposed Hell, coming around to self-acceptance; embracing that she's both a pathetic and horrible person, and coming to understand that her wicked acts and behavior have no real justification but she sticks to them any way purely because she enjoys herself best that way. She accepts the demon she allowed herself to become and that puts her in this Chaotic Neutral area for the rest of her existence where she interferes with the world of the living just to do cruel, selfish things to good people AND bad people alike. Sometimes her actions end up helping the side of good, other times they end up helping the side of evil, and either way is cool with Dahlia so long as she's having fun. XD