Vilest Things by Chloe Gong

Chloe Gong returns with power plays, spilled blood, and lethal romance in the thrilling fantasy sequel to New York Times and USA TODAY bestseller Immortal Longings, inspired by Shakespeare’s Antony and Cleopatra.
Calla Tuoleimi has succeeded in the impossible. Despite the odds, she has won San-Er’s bloody games and eliminated King Kasa, her tyrant uncle and the former ruler of Talin. She now serves as royal advisor to Kasa’s adopted son, August Shenzhi, who has risen to the throne.
Only Calla knows it isn’t really August.

Anton Makusa is still furious about Calla’s betrayal in the final round of the games. In an impossible feat, he took over August’s body to survive and has no intention of giving up this newfound power. But when his first love, the beautiful, explosive Otta Avia, awakens from a yearslong coma and reveals a secret that threatens the monarchy’s authority over Talin, chaos erupts. As tensions come to a boiling point, Calla and Anton must set their conflicts aside and head to the kingdom’s far reaches to prevent anarchy…even if their empire might be better off burning.