Fuufu Ijou, Koibito Miman. More than a Married Couple, but Not Lovers
The story is set in a high school where students are forced to live as a pseudo couple as a part of a curriculum. Jiro Yakuin is paired with Akari Watanabe, who is the complete opposite of him, in the traditional "marital training" class. At the suggestion of Akari, they start living as a pseudo couple in order to get the right to exchange pairs, which is given to the top performers. They practice various activities such as the first kiss in order to earn points, but as they come to understand each other's personalities and thoughts, they unintentionally become closer and come to like each other.
[Source: Crunchyroll News]