Beheneko: The Elf-Girl's Cat is Secretly an S-Ranked Monster!
Ｓランクモンスターの《ベヒーモス》だけど、猫と間違われてエルフ娘の騎士（ペット）として暮らしてますBeheneko: The Elf-Girl's Cat is Secretly an S-Ranked Monster!
The story
TVA knight is reborn as a baby behemoth that looks an awful lot like an adorable house cat. His situation grows even more confusing when a beautiful elven adventurer mistakes him for a furry feline and adopts him as her pet.
(Source: HIDIVE)