Yue Fei had seen the disaster of the Dragon City. She cried a lot on the day she found out that her family was destroyed and her city was destroyed.
The day she saw it, She took an oath to find the person who did it and to kill them. She was filled with anger and hate towards the person who had destroyed everything of her.
Her house, as well as her city, were left in Ruins. All her family members were killed, including her brother, who was the Second Prince.
After a few days, she disappeared. No one knew where she went.
The Eldest Prince became the new king of this Unranked Kingdom and started his efforts to get the Kingdom back on track and to search for his sister, who had disappeared.
The whole thing was a mystery. No one knew how, in a single day, a Third Ranked Kingdom lost everything.
Only the Nineteen Major Sects of the Continent had an idea about what might have happened, but they didn't bother telling these lowly people who they considered ants.