A Crimson Star (2018)

When fourteen-year-old Yo is hospitalized she gradually develops feelings for Yayoi who is a nurse tending her. However, Yayoi leaves the nursing profession in favour of prostitution. Yo is disappointed, but turns to the older woman after she is the subject of unrequited love from her mother's man. The two grow closer and Yo is about to find out what motivates Yayoi.