Voir Yosuga no Sora: In Solitude, Where We Are Least Alone, Season 1 - Episode 10

Haruka tries to explain to Sora his relationship with Nao, but Sora is always at the back of his mind. Haruka suggests a date with Nao, but cannot bring himself to tell Sora about it, even going so far as to disguise it as time with his friend Ryouhei. The next day Nao notices that Haruka tries to hide their date from Sora. The relationship is taking a downward turn.