Tsuma no Haha Sayuri  

Sayuris Mother In-Law, 妻の母さゆり, Sayuri's Mother-in-Law, My Wife's Mother Sayuri

The protagonist of the story is a white-collar employee. He has a spouse who leaves home, leaving him feeling lost and unsure of what to do. In his desperation, Sayumi, his wife's mother, contacts him, offering to take her place in their relationship. As they live together, he and she develop feelings for each other.