Ayanda, an orphaned student of Dark Dragon Academy, seeks a mysterious companion beast to tame in order to free himself of being unable to contract even a common beast, and being constantly ridiculed as being useless. He ends up contracting Levy, a Leviathan who was sealed away for ages, who turns out to be a powerful mythical companion beast, but he needs to find a way to restore Levy's original form in order to gain true mythical power.