Appears to have a close relationship to the former Heretic God, as she wields his sword Ame no Murakumo no Tsurugi, and calls him Grampsy.
Ena first thought of having a relationship with Godou as simply an assignment, a marriage of convenience nothing more. However, after his battle against Ame no Murakumo no Tsurugi, she has seemingly fallen in love with him. She has no problems showing herself in the nude to him. By the end of series their relationship get so intimate that they have sex after godou back to home (his universe).
The two have something of a rivalry because of Ena's near defeat of her while in the Netherworld, and because of her romantic interest in Godou. Erica considers her to be the toughest rival in the group because of her innocent and unpredictable nature that even Erica has a hard time guessing.