HP Fanfiction: Nancy's Perilous Mystery

At the beginning. The framed Demon King swore, "I will rule the world again!" The betrayed Rose sighed, "For the one I love, I don't want to leave!" The mastermind pulling the world's strings pondered, "I need to find someone to teach the protagonists how to live a proper life." 1984. Tom had a secret: he wasn't a black cat. Inside, he was a Demon King. Nancy had a secret too: she was a witch, and she was reborn. Merlin said, "Young people shouldn't be so rigid. Who in this world doesn't have secrets?" 1994. Harry had a dream: he would become a hero who truly lived up to the name, the Savior. Nancy had a dream too: she would become a witch without relying on a pact. Tom said, "Pah! Without a Demon King, you can't get anything done!" 2004. Mr. Black Cat was melancholy. "I've been trying so hard to live a good life. Why can't you love only me?" Mrs. Black Cat was baffled. "I've been trying so hard to live a good life with you too. Why can't you feel my love?" The little black cat was mortified. "Stop staring, everyone! These are my silly dad and mom. Can I admit it already?" The former Demon King, once a black cat, fumed. "If I'm going to destroy the world, I might as well start with this little brat at home!" And so, this is the story of a soul-bound Demon King who fails at making a comeback, a reborn witch who shines for love, and how she helps save the world along the way. Theme: