The following article contains spoilers from Shadow War Zone #1, on sale now from DC Comics.
Even though she is the daughter of classic Batman nemesis Ra's al Ghul and the mother of his son Damian Wayne, the past of the occasional villain Talia al Ghul is shrouded in mystery. Her upbringing under her father has made her the woman she is today, but much of her past is still relatively unknown. New context may have been added to explain her treatment by her father, however, in the story "Inner Demon" that appears in Shadow War Zone #1 (by Nadia Shammas, Sweeney Boo, and Becca Carey). As it turns out, Ra's may have made a deal with the devil to ensure that Talia's survival early in her life.
A look into Talia's childhood showcased her first meeting with Mother Soul, who informed her granddaughter of her first few days of life. Talia had been born weak and was slowly dying. Ra's, in a desperate attempt to save his daughter, used the Lazarus pit to give her the strength she needed to survive. In doing so, the story heavily implies that Ra's formed a bond between Talia and the demon that lived within the pit. This explains much of his behavior towards her, and possibly even her own actions over the last past few years.
During Damian Wayne's participation in the Lazarus Tournament, it was revealed that a literal demon existed within the Lazarus pits, and had some kind of mystical bond with the al Ghul family. That bond lives within Mother Soul, plagues Ra's, is hinted to be manifesting in Damian, and now has a confirmed connection with Talia. Mother Soul's claims that there is a price for power suggests that Talia's life was not saved out of charity. The glow in her eyes is proof that she now had some connection to the pit and what lurked within.
Typically, users of the Lazarus pit emerge insane and violent, but healthy. Talia was only an infant at the time and appears to not have suffered any surface mental complications. However, there is evidence to suggest that the effects of exposure to the pit may be gradual instead of instantaneous.
The way Mother Soul spoke of Talia implied that a toll would be exacted at some point in her life. It is for this very reason that Ra's has sheltered her, treating her as if she were made of glass. It might not just have been motivated by fear for her safety, but also fear of what she could become. Talia has certainly become more evil with the passage of time, perhaps not of her own volition, but due to the external influence of others.
When Talia visited Mother Soul, she found the Lazarus pit that saved her life. While staring at it, the demon appeared beneath its surface and attempted to grab her. Mother Soul did not seem surprised by this, but the moment might have been more significant than anyone realized. The demon required countless deaths to physically reform itself, yet in Talia's presence, it manifested enough to try and grab her.
All of this suggests that the demon will try to claim Talia for itself eventually. What it intends to do with her is unknown, but even Ra's seems to fear the possibilities. Although his intentions were noble when he attempted to save her, Ra's al Ghul may have inadvertently done more harm than help to the very soul of his beloved daughter.