Don't Touch the Bride! My Son is a Murderer (1981)

Three years have passed since the suicide of Kayo, the wife of sales manager Hagio of Kaihara Publishing. That day, Hagio is surprised to welcome Kaihara, the company president, back from London. Kaihara has brought his wife, Maki, who is like a daughter to him. Before long, Maki and Hagio's son, Kazuhiko, fall in love.