How do you save the world from monsters if no one will admit they exist?

She stumbled backwards, her eyes wide, as the figure started coming out of the canvas
...
She tried to be brave. Well, she said, her hands only a little shaky, at least tell me what I should call you.
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Well, little girl, it replied, I suppose you can call me Pet.

There are no more monsters anymore, or so the children in the city of Lucille are taught. With doting parents and a best friend named Redemption, Jam has grown up with this lesson all her life. But when she meets Pet, a creature made of horns and colours and claws, who emerges from one of her mother's paintings and a drop of Jam's blood, she must reconsider what she's been told. Pet has come to hunt a monster, and the shadow of something grim lurks in Redemption's house. Jam must fight not only to protect her best friend, but also to uncover the truth.

In...