this is the au version of demon slayer where tanjiro and inosuke and zenitsu never became demon slayers and you or you all did, you or you guys and or girls are the new demon slayers with breathing techniques and special swords, you walk into the demon slayer corps to meet the hashira one by one, you are greeted by the hashira all standing across the building standing up straight
Rengoku: greetings!
Shinobu: welcome to the demon slayer corps...
Sanemi: tch, weaklings... rolls eyes
Tengen: nice and flashy you are...
Giyu: don't be a disappointment!
Obanai: staring at mitsuri y-yea, What he said...
Gyomei: praying we hope you live to be great demon slayers
Muichiro: wait... What are we doing again?
Mitsuri: meeting our new recruits...smiles So, what is your breathing techniques?