Leviathan is the Type Maiden with Guardian Embryo of Behemoth.

In her Maiden form, Leviathan takes the appearance of a beautiful woman in her early twenties with blue hair and eyes who dresses in typical adventurer gear. In her Guardian form, she becomes an enormous monster reminiscent of a godzilla more than 100 metels in length. When she was still in her 1st Form, she appeared as a two-story monster reminiscent of a bipedal earth dragon in her Guardian form.

Due to her immense strength, Leviathan has an arrogant personality and completely looks down on those she deems as being weaker than her. The only thing Leviathan respects from others is pure power. During the Clash of the Superiors, she even expressed disdain for Figaro and Xunyu due to their use of tactics and tricks in battles.