METAMORPHOUS DEMON OF CATEGORY-A

He is the main villain of Demon Slayer (Metamorphosis).

STORY
Originally they were just two nocturnal demons who escaped severely injured from an unknown territory, finding refuge in a nearby facility that was one of the 3 zoos of the Khatsam family, the pair did not know about it. For a week, the demons covertly observed and analyzed everything, the different functions of the park, the schedules, the staff, among others. Until one night, when the park chose to close, they took advantage to devour all the animals in a cunning and thorough manner before dawn. At the moment, their only focus was devouring animals. On their journey, they found the other 2 remaining zoos and took it upon themselves to satisfy their appetite. Little by little, they discovered their own abilities, such as: transforming into animals "only those they had devoured", regeneration, and regurgitating demons of their own kind. As there were 10 demons, they began to devour people, as their appetite increased progressively, thus acquiring the new ability to imitate voices and communicate in human language. As the days went by, they had already regurgitated more demons, thus reaching a total of 22. The leading pair of demons met and gave instructions to the rest of the demons to disperse in pairs everywhere, in order to acquire greater power. However, one night, everything changed, while the main pair was exploring very distant territories, they ended up being killed in an intense battle by a peculiar hunter. Thus, only 20 demons remained, unfortunately, these were not capable of regurgitating demons of their own species, but totally different ones that looked like a mix of animals, lacking power and abilities.