Pin Off, Queen On

Silia sealed the soul of the Red Dragon into her daughter Luna, turned her own spirit power into a pin to hold it down, and told Luna never to take the pin out. The Spirit clan had been raised for generations to keep the Beast King, the Red Dragon, suppressed. Silia gathered the strength of the whole clan against it and got its core out, and that was as far as she could take it, so the soul went into Luna and the Spiritseal Pin was left with her to keep the dragon's power down. Luna was born with ability of her own, and the pin holds that down along with the dragon. People treat her as useless for it and she takes the humiliation without arguing. She works out that she can draw on the dragon's power inside her, and she leaves the pin alone anyway, because of what her mother told her. Then her people come under threat and she takes it out, which frees the dragon's power and something larger behind it.