Even though in her heart she wanted to reach out and playfully mess up his hair, she refused to admit it out loud. No good friends would act like that, and just because he didn't follow the rules of how good friends should behave didn't mean she wouldn't.
Obedient children get rewarded.
This was the excuse Bai Shihan gave herself when they were together. The so-called reward was just her own internal definition.
Chapter 50