Let spent a day behind iron bars before being moved to a solitary cell. For the first time in a long while, Let had ample free time, which he decided to use by focusing on mastering control over mental energy.
Within five days, he gained sufficient control over his mental energy and began to slowly understand the origins of mental and spiritual energy.
Mental energy was generated by the brain and was used for all mental activities. It also played a significant role in the formation of new memories.
Spiritual energy, on the other hand, was essentially produced by the soul and served as the source of emotions. The soul thrived on memories, which explained why memories faded over time.
Increasing the production of mental energy indirectly boosted the production of spiritual energy, but this came with a minor drawback. Boosting mental energy production naturally caused the brain to require more energy.
At the moment, Let had no control over life energy. Even if he gained control over it, producing more life energy would require consuming more food, making this unsustainable in the long run.
If he were in a fantasy world, he could solve this issue by consuming stronger monsters. But here, that wasn't an option. Therefore, he needed a method to convert spiritual energy into life energy.
Let spent the remaining days trying to externalize his mental energy. Mental energy and life energy attracted each other, and when they collided, bioelectric energy was generated, which then transformed into heat energy, destroying both forms of energy.
While attempting telekinesis, Let accidentally discovered how to steal life energy from other beings.
He would encase a fragment of mental energy in a thick layer of spiritual energy. Once it left his body, he would direct it into another being's body. By thinning the layer of spiritual energy, the fragment of mental energy would draw the life energy toward itself. Then, he would retrieve it along with the victim's life energy.
With minor adjustments to this method, it was also possible to transfer his own life energy to a target. However, the downside was that this process was mentally exhausting. Additionally, others could feel the spiritual energy as a tingling sensation.
Let discovered that telekinesis was possible, though the fact that he wasn't even strong enough to move a piece of paper was a bit discouraging.
This marked the 10th day of his captivity. It was finally time for his trial, and the others escorted him to court.
Let said nothing during the trial, choosing to remain silent in the face of all accusations. The judge had a headache, and the state-appointed lawyer had already given up on defending him.
The court decided to fine Let, but when he requested a prison sentence instead, claiming he had no money, everyone fell silent.
As a result, he was sent for a psychological evaluation to verify his mental health. Surprisingly, the records confirmed that Let was mentally sound.
Investigations revealed that Let was not a citizen of any country. This revelation was reported to higher authorities.
Some began to suspect that Let was a monster disguised as a human. Consequently, various samples were taken from his body for DNA testing. Knowing resistance would be futile, Let did not resist. Since he was from another world, he suspected his DNA would differ from others, but they would test him regardless.
This time, Let was held in a more secure cell. Escape seemed impossible, not that he intended to try.
He decided to use his current free time to master life energy.