When first meeting Koichi Sakakibara, she strangely requests to shake his hand. She then asks if this was the first time he had been to Yomiyama. Later on, it is revealed that the reason for these strange actions, is because she believed that she had met him by the river in Yomiyama, one and half years ago, after she accidentally kicked a can into his head. But Koichi does not remember this ever happening.
Izumi was nominated, by herself, as the "Head of Countermeasures" for class three. The reason for this, is that she believed that some of the others in class three did not strongly believe in the calamity, and that she needed to protect everyone. Because of this strong sense of pride, she felt at fault when the calamity started.