Brunhild the Dragonslayer

She was called the Dragon Princess by her people, sometimes with contempt, and sometimes with reverence. But 700 years before the Empire's cannon pierced the dragon's breast, there was another girl. Threatened by an evil dragon, the people of a small kingdom formed a pact with a Divine Dragon and flourished under its protection. Brunhild is born into the house of the Dragon Priestesses—the only ones in the land who can understand the dragon's words. Like her mother and her mother's mother before her, she serves the Divine Dragon, cleaning his temple, listening to his sacred words, and gratefully offering him tribute: seven people every month.(Source: Yen Press) Note: The setting is 700 years before the first published novel.

A century ago, the divine dragon sealed away the Dragon-Slaying Queen as revenge against the kingdom. But through the dedication of the queen’s successors, the kingdom has enjoyed great prosperity. Kriemhild, the daughter of the fifth queen, ascends to the throne with the same determination to protect the kingdom. Her elder sister Brunhild fell victim to the corruption of divine power, much like predecessors. Bearing that burden, Kriemhild steps into the throne room. But what awaits her is the kingdom's greatest darkness, known only to those who become queens.(Source: Yen Press)

The manga adaptation of the award-winning light novel! Eden is a place of perfection, protected from outside harm by the silver dragon. In this idyllic land, the dragon raises a human girl found on the island's shores as his own. But when the dragon's life is mercilessly snuffed out by human machinations, the girl must choose whether to heed his dying wish and stay the course of righteousness…or walk a path of vengeance. (Source: Yen Press)