Original title: 兄嫁とその母 ～居候していた兄の家に嫁の母が転がり込んできた結果www～
The protagonist began to live with his brother and sister-in-law due to entering university.
However, he was moved by his brother'wife Eriko, who used to be a model.
One day, her mother Marino fought with her husband, left the house and came to live with them.
That event created ripples, like a stone being thrown into quiet water, and started to affect their relationship...