Chaos Magic (The Forbidden Kingdom)

Carmell Ira, a 21-year-old PhD student, is obsessed with otome games. But her life takes an unexpected turn when she's brutally murdered by her boyfriend, Milo. She soon finds herself in the body of a young woman named Merrida, destined for a grand fate in the game's storyline, a game Carmell never got to play. All she knows is that she wants the cold Prince Darrius at any cost, and she has to find a way to get into the game's Forbidden Kingdom, which was conveniently cursed before all of the royal children, apart from Darrius, were born.
The glaringly obvious line drawn between nobility and commoners throws Carmell off, and in the first week, she breaks most of the unspoken rules. As she navigates this new world while attending Infini Academy's insane classes, she uncovers a dark secret about the demise of the forbidden kingdom and the rise of the current royal lineage. Carmell will find that she has more in common with the game and its royal families than just parading as the main character to form unbreakable alliances and restore her kingdom. Her destiny goes beyond the kingdoms of Patience, and Darrius will be the one to follow her into the darkness of their fates as soul mates and rulers.