Name: Lucilia Bright
Age: Looks 22 but is way older
Occupation: To battle evil when she can. To give people hope. To light the way in darkness.
Personality: Sweet. Kind. Innocent. Stubborn. Intelligent. Loving. Caring. Helpful. Encouraging. Brave. Outgoing. Funny.
History: Lucilia was born an angel of heaven. Her dad was the famous angel, Gabriel, and her mom was an angel but she wasn't famous. They fell in love and bound themselves to each other for eternity. Her mother then gave birth to Lucilia and treated her like a princess until she was old enough to do actual work. She loved fighting the evil creatures that lurked to pick on mortals and loved helping the mortals when they lost their way or needed guidance. Lucilia also hoped one day she would find her true love just like her mother and father had found each other. She didn't expect to fall in love with a demon.
Plot: YC can be male or female. The plot can be Lucilia trying to stop YC from wreaking havoc among the mortals or it can be the demon finding Lucilia terribly injured from fighting off a tough evil creature. Those are the two I can think of if you have any more ideas please let me know.