Kobeni Yonomori, who has just turned sixteen, is shocked to learn she has a fiancée named Hakuya Mitsumine who, along with his little sister Mashiro, come to live with her and her older sister Benio. …

As Mashiro tries to come to grips with Benio's popularity at school, Kobeni continues to try and remember about Hakuya. Later, Mashiro gets spooked at the thought of aliens existing. Meanwhile at scho…

Whilst Benio finally gets Mashiro to come to the student council room for tea, Kobeni goes with Hakuya to buy some ingredients for scones. Curious as to why Hakuya is so thoughtful of her, Kobeni asks…

The morning after learning about Hakuya, Kobeni ends up with a fever due to her weak body. As Benio informs Mashiro and Hakuya about what she told Kobeni, she blames herself for Kobeni's accident back…

Kobeni learns about a member of the Mitsumine family coming over, along with the fact that Mashiro is nine years old. Whilst shopping for supplies for her guest, Kobeni comes across a young woman who …

Kobeni's mother, Akane, who had always known the Mitsumines weren't human, tells Kobeni that she is no less thankful to them for saving her life. The next morning, Kobeni tries to learn more from Haku…

Student Council secretary Konoha Suetsugi feels some hostility towards Kobeni and Mashiro because of their closeness to Benio. Newspaper Club member Niko Ōno offers to help get some dirt on them, thou…

As Kobeni decides to keep Konoha's true identity a secret from Benio, Niko continues to investigate her, despite warnings from Hakuya. Later, Mashiro and Konoha find some time alone to confirm they ar…

As Mashiro informs Konoha about Kobeni and Hakuya's engagement, Hakuya chases after Kobeni, assuring her that he is already engaged to her. When Niko overhears this and asks if they are dating, Hakuya…

Benio seems to grow colder towards Hakuya, who seems a bit downhearted when Kobeni denies confessing. Meanwhile, Kobeni clears up the misunderstandings surrounding the engagement with Konoha, who atte…

Hakuya is troubled over what gift he should get for Kobeni to make up for White Day. Meanwhile, Mashiro is almost spotted using her powers by Niko, who becomes determined to investigate the existence …

As Kobeni worries about Hakuya and Mashiro, the only clue she has being a text saying they had gone back to the mountains, Mayura encourages her to go to the mountains herself to learn the true story.…