Sennousare Kaketeita Akuyaku Reijou desu ga Ie de wo Ketsui Shimashita.

When Marianna suddenly realizes she's living inside the novel she once read, panic sets in—her doom as the villainous lady is just around the corner. Desperate to dodge her fate, she locks herself in her room and vows to never leave, refusing to play any further part in the story's final catastrophe.