Shingeki no Bahamut: Genesis

Synopsis

The demon Azazel seeks the council with the demon clan's leader, Lucifer, but is turned away to capture the God Key that escaped his grasp. Favaro and the rest of the group are captured by knights and presented before the King in Anatae when three angels appear; they confirm that Amira is half angel and demon. The King orders their deaths, but the angels proclaim they must be kept safe as the demons are trying to revive Bahamut. Favaro, Kaisar, Rita and Amira are permitted freedom within the capital, but cannot leave, causing Amira to insist Favaro take her to Helheim as he promised. Favaro says it was only because of her curse and he's done with the dangers she draws, causing her to storm into her room calling him a liar. The angel clan schemes to use Amira to their advantage as her emotional state is tied to the God Key she is now the vessel of. Favaro encounters Jeanne who explains to him about Bahamut's original sealing and the legendary knight, a saint, who will be the one to seal Bahamut again. In the cover of night, Amira is lured from her room by a cloaked figure who possesses the same pendant as her, leaving her to wonder about his true identity. At the same time Azazel prepares his attack on the city.

(Source: Wikipedia)