Taboo Charming Mother (2003)

On the outside, it seems as if the Amamiya family of Enbo is a picture of happiness and stability; Yosuke is a successful businessman, having recently been remarried to a beautiful wife named Misako. Their son, Kazuhiko, is in college.

But for Misako, things aren't so fine and dandy: Kazuhiko is cold and distant toward his stepmother; the workaholic that is Yosuke doesn't satisfy his wife in the bedroom; and Misako receives menacing phone calls from an unknown stalker while the two are out. As Misako grows dissatisfied and her safe haven begins to crumble, she is drawn into a forbidden love that reveals her darkest and most illicit fantasies.