I'm a Behemoth, an S-Ranked Monster, but Mistaken for a Cat, I Live as an Elf Girl's Pet

An urgent message arrives for Aria and her friends—Vasargo of the Four Fiends is trying to obtain the Philosopher’s Stone, and he’s appeared with his troops in Aria’s hometown. With her companions in tow, Aria rushes back to the village and reunites with her mother, Leona. Together with Leona, now a captain of the Amazoness Corps, the group braces itself for the enemy’s attacks. It’s finally time for the decisive battle!

After defeating the Four Fiends and defending the elf homeland, Aria and her friends receive a new request from a pair of visitors. Mai, a time traveler from the future, and hero Ciel ask for their help in suppressing the demon lord Belphegor, who has emerged from the world of the future. Thus, the party crosses the ocean and arrives in the Kingdom of Urscula!

Aria’s party makes their way through the sealed labyrinth, finally reaching the dwelling of Belphegor, one of the Seven Great Demon Lords. Her abilities have grown all the more powerful since the old days… Can our heroes come out on top?