Little Dream's memories had been sealed away. This she had seen before. She was unaware of how much blood the dream devil clansmen had spilled at the scene. However, based on what she had witnessed of Little Dream the very first time she had met, she could tell that the Dream Devil clan had done its fair share of cruel things.
However, those things had nothing to do with Little Dream. She had no wish to let Little Dream know of what happened before her seal.
Little Dream saw how strong Sima You Yue's reaction was, but she didn't think too much about it before she sent a strong attack his way. The person was no longer free to speak as he used all his strength to attack back.
Sima You Yue watched as Little Dream battled that person, and realised that while Little Dream was not weak, and the opponent was not as powerful as she was, he had a higher battle ability than she did. She wasn't able to take him down for the time being.