A dream and a meeting with a weird but nice Demon King changed drastically Uesugi Fuutarou, bringing him to become a demon capable of seducing women: an Incubus. Now all the girls look at him with desire and all, but what can happen when he will start to tutor a group of quintuplets?

One day, Fuutarou sees Nino being cornered by some creeps, looking scared and hopeless. He intervenes and saves her, noticing how she's touching her stomach. To his horror, he sees that she has some old scars on it, so she tells him about her dark past. Fuutarou then hugs her, promising that he won't tell anybody her past and that he will do his best to protect her from now on.

Fuutarou is sure lucky: first he enters in the room of his laziest student and then finds a particular book in that mess that is her room. A book that contains some interesting things about Ichika, which will change their relationship from now on. And it seems they will change it very much...

AU: It was Nino that met Fuutarou in that famous Kyoto trip, a trip that remained impressed in both their minds as a beautiful memory. And after 5 years, they meet each other again in the same high school, which allowed to know the other four quints. It seems that he will be also their tutor, but what can happen next?

After what happened before and after the school camp, two quints that disliked Fuutarou changed as it seems that a flame ignited in the heart of each one of them. Flames that burned due to their feelings for a certain young man. Their sisters are interested in him as well, but a strong determination is not to underestimate.

AU: Fuutarou and Itsuki played often when they were kids, arriving to the point of falling in love with each other and getting betrothed thanks to their fathers. The boy had to leave at certain point because of some family issues, but after 5 years he's back and found out also that he has to help not only Itsuki but also her sisters. What more awaits them?

Following the incident in which both of them risked their lives, Chizuru started to have some special feelings for Kazuya, which brought her to confess them to him, finding out that he felt the same way about her. Now they're a real couple, but what awaits them from this point on?