Asa made Enchou Kibou desu

Hidaka has never felt sexual desire toward anyone—until he experiences his first stirrings of attraction toward Mizuki, a sex worker who frequently uses the love hotel where Hidaka works part-time. Confused by these unexpected feelings, Hidaka finds that he still feels the same pull the next time they meet. But more than that, he begins to want to know more about Mizuki himself…

(Source: Kadokawa, translated)

Note: includes one extra chapter.