For the next few days, Derek did not bother trying to destroy more impurities in Lunar's body. He used this time to sit silently and alone in his room while he regained his lost strength.
Not only did he fix Sol's damaged soul, he fought Lunar and also fought the champion realm, before coming back to destroy Lunar's impurities.
He was completely depleted, both in body and soul.
Derek sat in silence for days in meditation to replenish his lost strength. While he could sleep like a normal human, Derek had gone past that level now.
With his soul damaged and his soul essence slowly fading, Derek knew his time was coming to an end. His immortal God soul would have allowed him to live forever if given the chance, but with the rate things were going he and Sol were destined to live up to the peak human lifespan or slightly above it if they were lucky.