When Lu Chengzhou came out after changing, He Yidu and Qin Fang had not left yet.
Sitting closely on the sofa, the two of them were looking at a post-it note.
Lu Yī said, "This note was placed under the antidote. It's most likely Gu-"
Halfway through his sentence, he noticed that the bedroom door had opened. Hence, he stopped talking immediately.
Qin Fang was not entirely sure that Brother Cheng had really forgotten Gu Mang. Looking at the post-it note in his hand, his gaze wavered.
Then, he stood up and passed the post-it note to him. "Brother Cheng, do you know what this means?"
As Lu Chengzhou finished buttoning up his shirt and straightened the collar of his coat, he walked to the sofa.
He did not take the note. Looking down, he glanced at the black post-it note.
The words were written in white. On the note there was a chemical equation.
[SiO2 + 6HF = H2SiF6 + 2H2O]
