Based on the adult manga by Nagare Ippon.

Ryuichi is a university student. He used to live alone and enjoyed his school life. But one day, his apartment was destroyed by a fire…. He reluctantly comes back to his house. But his house has been changed to a boarding house for girls…! It seems there is no place for him to live. But they all allow him to stay there together! His new life begins like this…. (Source: Himeya Shop)

Based on the game by Frill.

A Long time ago, a curse was cast upon the Rindo family. The curse: the family could only give birth to girls. The only way to temporarily lift the curse was to have a child with someone from the Hizuki family. Once the curse was lifted, it would haunt the family again every 3rd generation. Many years have passed and now, Naoto Rindo will be the unfortunate one. His former fiancé, Suzune Hizuki has passed away due to a tragic accident and now he must impregnate one of the other four girls from the Hizuki family, however, time is running short. But wait, did Suzune really die? Mysteries abound around what exactly did happen and will happen since Suzune is still alive.

Long time ago, the Rindo family was cursed by a monster. Since then, new born babies have been girls. To break the curse, they had to marry persons of the Higetsu family who have strong spiritual power, and have to bear a child by the next red moon. Now, the curse befalls to Rindo Naoto. In order to break the curse, he has to beget a child with one of four sisters of the Higetsus. (Source: AnimeNfo)

The family holiday didn’t quite live up to Airi Akizuki’s expectations. Her stepfather, Kouzou Akizuki, decided to take her on a weekend trip to a ski resort—after all, nothing brings a family closer than shedding some sweat under the crisp winter sky. However, as it soon turns out, Airi is not the most skillful skier out there. Moreover, as the wind picks up and a snowstorm looms on the horizon, the pair finds themselves trapped in a chilly cavern. They are losing heat at a frightening pace, but there is one activity that will keep them warm for sure. [Written by MAL Rewrite]

Appalled by her father Kenichi’s carnal desires in targeting her younger sisters, Haruka Makino decides to become a “sacrifice” and sate her father’s incestuous libido alone. However, instead of solving the problem, her sisters begin to think that Haruka really plans to seize their father all for herself. [Written by MAL Rewrite]