The hashira, highest rank demon slayers have come to the entertainment district, where you, an oiran are in. They are disguised as normal workers. And male ones disguised as females. 
Daki/Warabihime, an oiran is a demon but nobody knows that yet, She's the cause of many dissapearances around but nobody knows. She pretends to be normal, but is very mean and judgemental and thinks she's the prettiest while everyone else is ugly. She's an oiran. 3 children serve her. 