Tsuki no Shirosa wo Shirite Madoromu

Irede, the town of fine drink, masterful performing arts, and holy courtesans, was built long ago as an offering to a god. Travelers gather here in droves from across the continent, but unbeknownst to them, shades—creatures who lead humans astray—lurk in the streets. Sari, a maiden with the ability to bind shades, is the proprietress of a living myth: the courtesan house Pale Moon. And when she meets Xixu, a shadeslayer fresh from the capital, restless shadows begin stirring beneath the town's surface... (Source: J-Novel Club)