Big-breasted Sucking Slave (1996)

Yuri Sakita takes on a live-in babysitting job to pay off her boyfriend's debts. However, the child she was looking after was the doll that Seiko, the deranged wife who had lost her beloved in an unfortunate accident, cherished. While feeling lost, she continued her part-time job, and Yuri began to feel affection for Masanobu, the husband who warmly watched over his wife. However, one day she learned of Seiko's scheme, who was actually only pretending to be mad. And then he gets framed for a murder-suicide scheme by her, who wants his insurance money...