Sayonara Color (2005)

Shohei works as a doctor in a seaside hospital. One day, a new patient is admitted to the hospital with ovarian cancer. Shohei is surprised to recognize Michiko, his first love from high school. Shohei has been leading a dissolute bachelor life, paying for the company of high school girls and dating an older woman who works in a local bar, but in reality, for the last twenty years, he has not forgotten Michiko. Unfortunately though, Michiko doesn't remember him at all. Shohei becomes more and more persistent in his attempts to get her to recall their past. At first she is annoyed by his overtures, but gradually warms to the doctor. Under Shohei's kind and patient care, Michiko's condition improves and her cancer becomes operable. The operation is a success, but now Shohei himself learns that he has terminal cancer.

Unfortunately the movie Sayonara Color is not yet available on HBO Max.