For a while, it was rather difficult; she still behaved coldly in front of her classmates. But gradually, as time went by, the situation changed. She hasn't opened up to others aside from him regarding sensitive topics, but she no longer treats people as the enemy. For him, that was already a considerable improvement.
"Back when we were working together. I tried." Yuhi mumbled.
Sumire laughed. "Indeed you did; it almost worked, Yuhi. But you left me."
It pained him just thinking about the time apart from her, let alone hear her mention it.