As a lich, Charlie's mind and soul are bound to one another. His mind and conciousness is a manifestation of his soul, which is stored in his phylactery, so without the soul, his mind wouldn't be able to exist, however the mind controls the soul, which is Charlie using his powers, and just generally being a lich.
However, the soul still has a presence. Due to the horrific nature of the ritual to become a lich, Charlie's soul radiates death, highly concentrated, and could be viewed by anyone with the power to see souls as similar to looking into a void, and Charlie is generally an evil presence to anyone who can detect such things. People who connect to Charlie's mind will often also end up interacting with his soul, which can sometimes be heard as words via those who connect to Charlie. Whilst Charlie's mind is definitely and permenantly in control of the soul, it is still there.
Whilst Charlie doesn't sleep, or dream, he can meditate, which he can leave at any time, and in this state those with the power to enter dreams can enter his 'mindscape' which resembles a snowy forest with trees made of bone. The sky in this forest appears to be considerably lower than a real sky, and is used to mask the presence of his soul inside his mind. Inside his own mind, Charlie also has total power. Within this mindscape, he cannot kill anyone who enters his dream, but they cannot leave without his say-so. If he were to stop meditating, they would be ejected from the dream as if they had left themselves, and not be trapped.
