Inner Monologue
Inner Monologue is an amazing experience where normal human beings can discuss or describe things to themselves. These "discussions" can be as simple as a monotone voice but can also be as intricate as vast adventures within a three dimensional world that the human creates with just the power of their own mind.
People who do not have an inner monologue are in a sort of poverty where they lack even the concept of what an inner monologue is. Much like a deaf man trying to imagine what a symphony sounds like.
Description
Anon offers a description of his own inner monologue:
I can "hear" it in my head. I can cover my ears and still hear it. It has an accent, I can raise the "volume", it can scream or whisper. It can talk in multiple languages. It doesn't control me, I control it but I can assign it a "separate personality" and split it into multiple actors. As a consequence, I can simulate a conversation with multiple characters in my head. It can also become female at my will. I think I can do this for up to 5 characters without any mental effort. 
Anon goes on with his description, adding circumstances where inner monologue is not useful:
When not in theater mode I the only things I say to myself are plans for the future e.g. what to eat for lunch. It doesn't activate when doing mundane stuff like opening doors or saying hello to other people. It's less active when talking to other people. I need a big pause between sentences to activate it. Combine that with my ability to visualize things and I can have a whole movie set complete with props in my head.
Silencing
Going to the next level, humans who can silence their inner monologue at will are just that much more special. Whether they use prayer, breathing exercises, or can do it on their own with just the power of their mind, finding that "quiet place" allows these people to be able to experience the calm world of an NPC while also enjoying the power of the inner monologue.
Aphantasia
I have aphantasia. I don't care. I didn't even know I had this "condition" until I saw this meme on the internet last year. Not everyone's brain works the same way. I have a STEM PhD so it's not like I'm retarded. - AI based text response
There is no such thing as a medication or medical technique to give a soul to a soulless being. You are an NPC; a side-character. A form of biological AI.
I know that a car has 4 wheels, generally 4 doors, a boot, a windshield, wing mirrors, headlights etc, but I can’t imagine a car and see it. - A sad sufferer of ahpantasia.
The Cope
Below, you will find the standard cope that most NPCs use.
Pretty sure all this "aphantasia" and "no inner monologue" shit is just a big retard misunderstanding of semantics. These people literally think that when someone says "inner monologue" they mean they hear an actual voice in their head, like with their ears.
But that is literally what it is.
It's the same with mental images. These people have dreams when they sleep at night. They just don't understand the difference between mental images and actual sight.
Dreams have nothing to do with this. Inner monologue allows for images within that mind that are as realistic as actual vision.
I've suspected this for years. These aphantasia idiots just don't understand what is being said, which is arguably just as if not more dumb than having aphantasia.
I agree with you here.
Drugs
There is always some dumbass out there telling people that drugs like magic mushrooms or DMT will "cure" NPCs of this malady. They are wrong. A true brain Chad does not need chemical stimulus to achieve inner monologue.