Nanamori Seira

Nanamori Seira is the new heroine of the series. She is Kasane's classmate but not her friend. However, she used to refer to Ibuki as a sister. Seira used to be friends with the whole Hinata family, however, an accident set out their relationship to worse, and she became like what she is today. She and Ibuki are childhood friends

Seira appears antisocial and cool and really mature for her age, however, she is actually pretty clumsy. She loves watching the starry sky in the park every day. Seira also acts sometimes a little bit old-fashioned due to living with her grandmother.