Ichiko (2023)

Kawanabe Ichiko has lived with her boyfriend Hasegawa Yoshinori for 3 years. One day, Yoshinori proposes to Ichiko, but, the next day Ichiko disappears. Yoshinori panics and doesn't know what to do. At that time, Detective Goto Shuji visits him. The detective shows a picture of Ichiko to Yoshinori and asks who is this woman? Yoshinori traces her whereabouts. He meets people who have had relationships with her like her old friend and high school classmates. Yoshinori learns about Ichiko shocking past.

(Source: AsianWiki)