Yosuga no Sora Episode 04
Haruka's Heart (K4)
Name in Japanese ハルカズハート
Romaji Translation Harukazu Hāto
Air date October 25, 2010
Production Staff
Episode Guide
Previous Yosuga no Sora Episode 03
Next Yosuga no Sora Episode 05
Theme Song
Opening Song Hiyoku no Hane
Insert Song Tsunagu Kizuna
Ending Song Pinky Jones

Haruka's Heart (K4) is the fourth episode of the anime series Yosuga no Sora. It talks about how Kazuha solved her problems and inner struggles by the help of Haruka.


On their way home from school, Haruka and Kazuha are interrupted by a frantic Yahiro, who is concerned over the non-appearance of the always-responsible Akira as usual. They discover Akira is masturbating at her home, collapsed due to exhaustion, and Kazuha proceeds to blame herself and her infatuation with Haruka for not noticing Akira's condition. Akira recovers a few days later, but confronts Kazuha about her abandonment of Haruka and the inappropriate sense of guilt she feels regarding their father's actions. Realizing the truth of Akira's words, Kazuha withdraws into a state of depression while struggling and was thinking about what to do next. The day of the festival arrives, and Kazuha works up the courage to appear, where she is reunited with Haruka. Haruka informs Kazuha that her father had been supporting Akira financially in secret all this time and, when Kazuha witnesses her father praising Akira, she realizes that she had misjudged him. Thus, she was able to move past her codependency towards Akira and pursue a relationship with Haruka. While she was playing the viola for Haruka and Akira, Haruka was thinking how he and Kazuha had sex the previous night...............


Name: ...(M4)
Name in Japanese: ...
Romaji Translation: ...
Quote of the Episode:- Trying too hard is just as bad as not trying.
English: ...
Japanese: ...
Romaji Translation:  ...



  • The arc ends with a sex scene with Haruka and Kazuha as the only two characters in that scene, and Kazuha playing the violin for Akira and Haruka.