Another secret

'..We found her, but in a pile of dead bodies.'

'Sumire didn't recognize me.'

The words Atushi said to him when he first started dating Sumire appeared in his head. When they first started dating, Atushi called him to have a private talk. 

'Can you still date Sumire despite knowing this? There is something we didn't tell you, Yuhi; you see, there was a time where some people kidnapped Sumire. Mamoru somehow managed to get her back, but when he returned, his illness had worsened. It was only a week after the two started dating.'

Yuhi frowned, just recalling the words Sumire and kidnap. During the time those two were captured, what exactly happened? It seems Sumire has no memory of this kidnapping; otherwise, she would have mentioned it.

The thing he asked Atsuro to investigate was the kidnapping. So why would Atsuro ask him to discuss the details with her? Unless she remembers everything.