The episode opens with Sora having a nightmare about her twin brother leaving her. She wakes up crying, and Haruka comforts her. This scene sets the tone—Sora is terrified of abandonment. Her famous line, “Haruka is mine,” is foreshadowed heavily here.
On Reddit’s r/anime and MyAnimeList, Episode 5 is rated 4.2/5—higher than the previous four episodes due to its atmospheric tension and bold narrative shift. yosuga no sora ep 5 eng sub bilibili