He knew that Mu Huan was disgusted by being with Mu Kexin, so he deliberately made Mu Kexin go head to head against Mu Huan. If he must panic, he also wanted her to be bothered!
Mu Kexin did not want to sit with Mu Huan, and there was nothing to apologize about. She knew that even if she did apologize, Mu Huan would not forgive her much. However, she could not do nothing about it. Hence, she could only stand up.
"Don't come over. It's impossible for us to be good sisters. We can't be good sisters in the past, much less in the future. So, stay away from me!" From the start, Mu Huan had made it clear that she and Mu Kexin were strangers. Their relationship wasn't good, so she didn't want to give her a chance to act like good sisters. Neither did she want Mu Kexin to act as a little white lotus and then make her as her sister look bad.