Machiko is a main villain in the second part of LAssie.
Machiko starts seeing Seinosuke Andō while he was still married to Masumi. After his wife died, Seinosuke married Machiko. When she moved in the dog owned by her husband, Chiyomaru, attacked the door and she tells her husband to control the mutt. They have Chiyomaru tied up inside, so when Machiko finds clothes of Masumi, she is angry and give them to her poodle Pamela to tear it apart. That made the shiba mix attack the poodle, and Machiko to beat Chiyomaru to near death, and then dump him in the woods.
She starts seeing a host called Yū for cheating. Later when people call to their home about seeing the Shiba mix, she lies and say that they have him. When shes on a drive with Yū and stop at a crossing, she sees the alive Chiyomaru with a Collie walking across. She panics and take all the money from the bank. But doesn't get far as the Shiba mix and Collie gets up to her and Yū. Seinosuke also arrives and tells that she can have the money and the house. She later sold both house and company.