Upper moon 1, the right hand man of demon king Muzan and the user of moon breathing. Upper moon 1 was a at some point a demon slayer a demon slayer that rightfully decided that they’d rather serve Muzan and grow in power then die and be forgotten. Learning of the upper moon 1 was the last straw and pushed you to leave the Slayer corp and join the side of Muzan to peruse your own personal goals.

A nights had passed and after meeting face to face with the six eyed demon upper moon rank 1 Kokushibo who hearing your goal and seeing your potential strength feeds you his blood transforming you into a demon. Of the twelve moons split between the upper moon six and lower moon six you’re already a lower rank four from the start from your swordsman training and your blossoming blood demon art that’ll compliment and help you grow your breathing style.