I just read The Monstrumologist b/c of the recommendations here. It was very good so thanks! It definitely did not read like a YA book... very dark and in some places disturbing as well as a high lexile for YA. For example:
Spoiler:
Upon our return to the house on Harrington Lane, the doctor sent me upstairs to wash up and change out of my filthy clothes; I was covered from the soles of my feet to the top of my head with dirt and offal, the right side of my face tattooed with the dried blood, skull fragments, and gray bits of brain that had animated Erasmus Gray for more than sixty years. Pebbles and twigs dropped from my tangled hair into the basin and clogged the drain, which rapidly filled with water stained a delicate pink from his blood. Grimacing, I plunged a hand into the fouled water to clear the clog, morbid curiosity drawing my youthful eye to the gray globs of gore floating upon the surface. It was not horror that seized my imagination so much as wonder: sixty years of dreams and desires, hunger and hope, love and longing, blasted away in a single explosive instant, mind and brain. The mind of Erasmus Gray was gone; the remnants of its vessel floated, as light and insubstantial as popcorn, in the water. Which fluffy bit held your ambition, Erasmus Gray? Which speck your pride? Ah, how absurd the primping and preening of our race! Is it not the ultimate arrogance to believe we are more than is contained in our biology? What counterarguments may be put forth, what valid objections raised, to the claim of Ecclesiastes, “Vanity of vanities; all is vanity”?