My Dad, Your Dad 3 (2019)

When Jane turns 18, she is to move out of her foster parents home. Begrudgingly she begins to look for a new apartment but her crush on her foster dad keeps her distracted from being too proactive. Unfortunately, because her attraction is too forbidden to ever fully admit to, Jane escapes into stories she finds online at her favorite site. Through the website she discovers that she's not the only young woman lusting after a forbidden man in her life. As her arousal grows, reading a variety of exploits from other women, Jane decides to reach out to a man she met on the site who wrote about his own attraction towards his former foster daughter.

Unfortunately the movie My Dad, Your Dad 3 is not yet available on HBO Max.