After Becoming the Saintess, Why Am I Still Being Coerced by the Princess?

[Pure Love 1V1]
After transmigrating into a noble lady who lost both parents, Lucía is forced into a political marriage by her wicked uncle. She secretly escapes, hoping to live a quiet life of her own.
But things spiral out of control when the kingdom’s princess seeks to use her against her family.
In an attempt to evade the princess, Lucía accidentally becomes the Saintess—only making the princess more determined to capture her.
Now she must cooperate with the princess using her Saintess identity, while carefully avoiding exposure…
However…
Your Highness, what are you doing? I am the Saintess!
As the princess locks the door and approaches her bed,
Lucía realizes… there may be no escape left.