The prison was still extremely quiet. Apart from the breath that sounded after more than a minute, no other sound could be heard.
This claustrophobic environment would undoubtedly cause extremely powerful mental torture to people. If anyone with a slightly weaker mind was here, they would feel like they were going crazy in less than a day. In less than three days, their mind might be on the verge of collapse.
According to the latest research report of the Milky Way, anyone, even the martial artist with the strongest mind, would be forcefully imprisoned in such an environment for more than ten days and their mental state would be the most completely damaged. It was basically impossible for them to return to normal in the future.
Chu Nan had been locked here for seven days.
