The Unseen World - The Demon of Pain. The Unseen World, #4

Daria believed the nightmare was over. After descending into the hidden alleys of Inferno, she sealed the Demon of Pain and silenced the last echoes of that cursed realm. The demons were gone. The suffering they ruled had been locked away. But when she returns to the world of the living, something is terribly wrong. The city breathes strangely. Smiles linger too long on human faces. Time fractures in reflections.
Children watch the world with eyes that seem far too old. And everywhere she walks, Daria can feel it - something spreading through people like a quiet infection. Then she learns the truth. The alleys of Inferno were never meant to be destroyed. They were the only places where the darkest pain of humanity could exist without consuming the world. Now those places are gone. And the suffering that once lived there has nowhere left to go.
It is returning. Through dreams. Through memories. Through the cracks inside the human mind. As reality begins to twist and collapse, Daria must confront a terrifying realization: the demons were never the true danger. Humanity was. And this time, Hell is not rising from below. It is awakening inside of each human being.