I Come from Hell

In order to prove the existence of the soul, scientists launched the "Hell's Gate" project: letting volunteer teenagers enter clinical death, explore the other side of consciousness and then resurrect them. The experiment was successful, and humans received some forbidden gift from the other side. However, the real world began to distort, and unexplainable "existences" appeared. Many years later, a young man returned from a collapsed future, determined to close that door. But the deeper he went, the more horrified he found that he was actually a part of hell...