Quick recap
Two months later, Tessa is getting ready to marry Jem, who is failing without the yin fen Mortmain bought up. Automatons attack the Institute, fatally wound Jessamine and carry Tessa off to Cadair Idris in Wales. Mortmain reveals she's half demon, half Shadowhunter. Will goes after her, and the two end up together. The group learns Jem became Brother Zachariah, a Silent Brother, to survive. Tessa takes the form of the angel Ithuriel, trapped in her pendant, and burns Mortmain to ash. Tessa marries Will, has two children and watches him die of old age in 1937. In 2008, she finds Jem again, mortal once more.
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