The player takes the role of Sakura Kouji, second son of the Sakura family and convenience store clerk. His day to day life as a young adult is pretty monotonous, as he wakes up, goes to work and then comes home. Most of the problems in his life stem from the fact that he is seen as the black sheep of his family, and gets the majority of his grief from his older brother Shuuichi and his aunt Yukari. Of course, Kouji's additional burden is the fact that he's in love with his sister-in-law, Kyoko.
Kouji's psyche has endured quite a bit of abuse throughout life, as he was always compared to his older brother (and put down for never being good enough to match Shuuichi). To our protagonist, Kyoko being married to Shuuichi is basically life kicking him while he is down. As such, he often tries to avoid seeing either of them, but rarely succeeds due to Kyoko doting on him the way an older sister would (not to mention Kyoko and Shuuichi live next door to him).
After Shuuichi suddenly disappears (leaving a note for Kyoko, asking her to improve herself and that he'll be back in two weeks), our protagonist gets dragged into a series of events that concludes with Kyoko signing up to the Yoyogi Housewife Training Academy in hopes of becoming a better wife for Shuuichi. As the academy only accepts married couples, she makes Kouji come along to pose as her husband.
Thus, Kouji's two-week training course at the academy begins. Outside of helping Kyoko (and in a way, realizing his dormant dream of having a relationship with her), his life becomes intertwined with four other women looking to overcome their own problems or move on with their lives, all brought together by the academy's mission.