Manga by author Kisa (きっさー)

Satou Sou is accidentally swapped with himself in a parallel world with a male/female ratio of 1:39. He finds a kind family and lovely women at the place where he was switched. Seeing the outside of these women, he's relieved to see that the number of men and women has changed, but not much else. However, their inner lives are filled with conflicts and troubles.