Seraph Eden is in the first order of the Hierarchy of Angels and is thus the leader of the entire angel army and is Goddess Ilias’ right hand. Eden is obsessively loyal to Ilias, always obeying her will and never thinking to betray her. She distrusts Promestein, a lower-ranking angel with her own motives, and Black Alice, the 8th Monster Lord. However, she grudgingly works with them on Ilias' orders.

Eden absolutely hates being called the “Third Great Seraph", "Third" or anything that seems to imply such, since Micaela and Lucifina became fallen seraphs and departed and thus Eden considers herself above her predecessors. Eden is first mentioned during the siege of the Monster Lord’s Castle, having sent Archangel Ariel to assist. However, after the Archangel is defeated, Promestein calls Eden a failure. Luka can't help but wonder who Promestein is talking to, but she doesn't say.

After Promestein retreats, Eden urges Ilias to punish her, but Ilias decides to let it go, much to Eden’s dismay.