| Akira Amatsume|
|First Appearance||(Anime) Episode 1|
|Portrayed By|| |
Akira Amatsume is one of the most important heroines in Yosuga no Sora. She is one of the most cute heroines of the series.
Having an innocent personality, Akira is much like an angel, she is the most lively of the heroines.
Due to her residence, Akira spends much of her time practicing the habits and traditions of a miko (shrine maiden), including performance of requisite ceremonies and holiday festivals. She shares the same father of Kazuha, though Kazuha's mother does not like this and had a little inferiority to face her, eventually convincing her father to disown her. In Akira's arc, it is revealed Kazuha's mother actually saw her when she was a baby and liked her. She is even was told that the pendent she wore was Kazuha's mother's pendent and was given to her when she pulled the pendent from Kazuha's mother's neck when she was a baby. She has short,brown hair and brown eyes.
- Mr.Migiwa (possible father)
- Ms.Amatsume (mother,deceased)
- Kazuha Migiwa (half-sister in the manga only)
- Mrs.Migiwa (step-mother,in the manga only)
- Yahiro Ifukube (Like an mother to her)
- She's one of two characters who've developed romantic feelings for someone but couldn't confess their love on account of speculation that their love interests might be biologicaly related and didn't want to commit incest.
- She's the only character in Yosuga no Sora to have been raised by a single mother.
- She's one of few characters to share a bath with their love interest.