C194 Gu Yin Ren Had Come to Visit

The moon outside of Duke Han's residence was as calm as water.

Su Tingchen and Shan Yunong refused to sleep in the study room.

"What do you mean?"

Shan Yunong said: "This herb and the grass orchid both have hallucinogenic ingredients. If given for long periods of time, it can cause damage to the nervous system, which means that the person's willpower is gone and can be easily controlled