Leviathans

Leviathans were the artificial dragons born from occult and magic. Created for fighting dragonkind, these "serpents" possessed bodies similar to dragons and shared their lives with witches/magi.

Humanity was forced to coexist with dragonkind in this century. Thus, the existence of 'serpents' became gospel to those who worry about the security of neighboring areas. Namely, those created through the ancient knowledge known as magic... the giant creatures named leviathans.

Artificial monsters created by magic to oppose the dragons. Witnessing their existence, the media called them "leviathans" in reports, even making up the nickname "serpents" for these super lifeforms.

Using an alchemical process only privy to SAURU, the ritual creates the physical body of the 'serpent' then links it to the candidate girl through covenant magic. If successful, she will become the leviathan's partner, in other words, a mage.