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If Tim Burton mixed Coraline and The Labyrinth together as a steampunk novel set in the Southwest, it would read something like HOUSE OF GEARS. Cool mashup.
Seventeen-year-old Juliet Loew's father and stepmother despair of a daughter who spends her time playing the cello, reading, and making monster-dolls for her little sister, Eustacia. Her parents tell her the cucuy - the bogeymen she models the dolls after - are dangerous monsters to be feared, but Juliet can't bring herself to believe it. After all, her older brother is a cucuy...which is one reason her parents like to pretend he's dead. But when a strange cucuy kidnaps Eustacia, their brother is nowhere to be found, and Juliet will have to rescue Eustacia all on her own. So far this is really good - you've got a lot of information here, but it's all well-written and engaging.
Her quest uncovers another life in the cucuys' steam-and-aether powered, nix the comma, yeah it's a long sentence but the comma messes it up clockwork world that Juliet doesn't remember - because her memories have been stolen by the people she thought she could trust. While trying to rescue her sister and regain her memories, she discovers a life of imaginary friends made real; family secrets stretching back centuries; a war to preserve the balance of light and dark in the human world; and forbidden friendship and love with Miss Locket P. Pick and Don Tomãs Scorpion, leaders of the resistance, who cast long and achingly familiar shadows across Juliet's forgotten past. Unsure who to trust (including herself), in the end Juliet will have to choose between her family and the fate of both worlds, and she'll have to decide if everything she's ever believed about herself is a lie. Again, you've got a lot of information in here but it's delivered well and in a flowing manner. I think it's great!
Entwining Southwestern steam- and clockpunk and historical dark fantasy, HOUSE OF GEARS loosely retells a beautifully nightmarish YA Cinderella in 121,000 words Your word count is high. Even for fantasy (which has wiggle room for world building) this is a long book to try to debut with (with a touch of genderbent "Sleeping Beauty" as well as several fractured fairytales and legends from Mexican, Judaic, and Slavic folklore) where Cinderella and the prince have known each other all their lives, Cinderella loves her stepsister, and the fairy godmothers and Prince Charming are nightmare creatures of Judeo-Hispanic legend. I'd say in this para you're actually muddying waters a little bit when that's the opposite of your intent. What you're trying to do is take a familiar tale and turn it on it's head with these comparisons, but you've already got three pop culture references in your intro -- to layer on quite a few more only lends to confusion. On the other hand I do like the touches of different cultures' folklore, yet I think they are still putting a little too much icing on the cake. I'd stick with what you've got in the first two paras and call it a day.