C27 Red-light region of the yin world

I patted my chest. I was really scared to death just now. That ghost official stared at me ferociously. My heart was about to jump out of my chest. However, one cry, two play, and three hanging up was really useful.

But why is it that even after Senior Sister and Senior Brother ate the Yin Dan, I was discovered to still have Yang Qi on me?

Just to be safe, I ate another Yin Dan