"Thank you," she said, stepping forward into Renju's room—which she hadn't ever been in, had she? It wasn't like Kozue spent much time visiting other girl's rooms, after all. She nodded her head slightly, and smiled, trying to account for Renju's apparent confusion about the situation with calm, confident friendliness. At least, in Kozue's lexicon of social interaction, saying er and looking surprised spoke to her of confusion, possibly discomfort. Kozue wanted to cause neither of these things.
"How are you?" Kozue was always one for pleasantries; they were a habit she could fall back on without really needing to think about in her conscious mind.
She smiled, and continued to surreptitiously check the room around her; pleasantry was a habit, but curiosity was in her nature.