I'm a Behemoth, an S-Ranked Monster, but Mistaken for a Cat, I Live as an Elf Girl's Pet[a] is a Japanese light novel series written by Nozomi Ginyoku and illustrated by Mitsuki Yano.

Written by Nozomi Ginyoku, I'm a Behemoth, an S-Ranked Monster, but Mistaken for a Cat, I Live as an Elf Girl's Pet began serialization on the user-generated novel publishing website Shōsetsuka ni Narō on August 19, 2017.

[5] It was later acquired by Micro Magazine who began publishing it with illustrations by Mitsuki Yano under their GC Novels imprint on March 30, 2018.

[7] A manga adaptation illustrated by Taro Shinonome began serialization in Hakusensha's Young Animal Arashi magazine on March 2, 2018.

[2] It is produced by Zero-G and Saber Works, and directed by Tetsuo Hirakawa, with Kanichi Katō in charge of series scripts, Tomoyuki Abe designing the characters, and Yūsuke Shirato and Oni composing the music.