Greater Beast Zelas Metallium (Juu-ou:Beast King)
Though Zelas is never seen in the series, she is mentioned by Xellos from time to time, and is partially seen in the opening to Next, the opening to Try and the final end sequence in Try. She's petite and blonde, and prefers to wear short dresses, mini skirts, and high heels. She wears multiple bangle bracelets around her wrists and ankles. She's a binge drinker and a heavy smoker. Zelas is also the youngest of the five subordinates. Her true form is that of a rather beastly looking wolf with wings. She resides on Wolf Pack Island which s not on any maps, but is said to be in the middle of the Demon Sea. Zelas is also said to be a good friend to Luna Inverse.
Zelas' agenda seems to differ from that of every other mazoku in the Slayers world. For that purpose she created Xellos from a part of her astral body making him both her priest and general, and very powerful in the process. No one but Xellos knows of Zelas' agenda. Her wars with the other subordinates continue endlessly. She is particularly hateful towards the Sea King Dolphin and drove her insane.