This is a fight between the Domum Furioum High Court Succubus and a Domum Nokte Assassin. This will not end will for the assassin.

Few things:
Each Domum (or House) has a High Court Succubus that are powerful in both magic and combat. Domum Furioum is a house of war, so her combat magic is on point.
The Assassin is wielding an Auraum Fel Longsword. The gold allergy of the Fel Devils is little known outside of their kind, but Auraum weapons are especially lethal because they ignore the Fel's natural healing abilities.