S1E10: Here Like Normal

Now it's become perfectly normal for Aika to read manga in Kouta's room. She brings all the volumes out to read them all at once in the living room, but the moment she sees the dark hallway, she becomes strange and dejected, returning to Kouta's room. Aika confesses to Kouta that she's scared of being alone. Kouta assumes she just hates being on her own, but it seems there was more to it than that...