A Game Cursed and Deadly by Ella Laurenti

A box of trinkets. A missing item. Find the lost piece, break the curse.

It should’ve been a walk in the park for Teizel, Prince of the Beyond. Instead, centuries later and with several innocent people’s lives on his conscience — if monsters even have one of those — he’s not sure there is a way out of the infernal game he’s been forced to play. That is, at least, until he lays eyes on Esmeralda. Beautiful, lonely, and in so much pain it calls to him like a siren’s song. The perfect candidate for his wager.
Moving back to the tiny hometown she escaped at eighteen isn’t the culmination of Esmeralda’s eight-year plan. But when her Àvia passes, she has no other choice. To someone as lost and crushed by grief as her, Teizel’s crazy game doesn’t seem so crazy after all. If she wins, she gets her deepest desire fulfilled. If she loses, she forfeits her life.
Teizel really shouldn’t get his hopes up. Except he can’t help the pull toward Esmeralda. With every clue to the game she unravels, she also uncovers a piece of him, bringing them closer together. As the clock ticks, Esmeralda may be onto more than just a missing trinket: she may have found the key to Teizel’s heart. Now, he must do everything is his power to ensure her success — not only for his freedom, but for her life, too.