The perspective shifts to Han Dong.
Having detected a strange shadow, he chooses to delve deeper into the opposite direction of the tunnel during the waiting period to investigate the shadow.
"Dead end... strange!
The shadow disappeared right here, theoretically, should this be a crossroad?
The shadow moved to the right.
Is it a ghost, or is there some secret mechanism or hidden passage here?"
"Little Demon Eye" looks towards the right side at a sac membrane (that has not yet cultivated a ghoul). The life-quality solution inside the sac is unique, preventing it from being seen directly through this fluid.
If indeed there is a hidden mechanism, there is a reasonable chance that it is hidden behind the sac.
After all, Han Dong can't see any 'secret compartment' in the area he can see for now.
Without hesitation, Han Dong reaches out behind the slippery sac... It feels like reaching into an animal's organs while conducting a biological experiment on a live subject.