The previous experiences were, in fact, unreal, and each character that appeared had a corresponding puppet.
Although they were not lifelike, the feeling of being stared at by so many eyes was eerier than real people.
And from Doctor Dorian's description, they were evidently an important tool in a mature treatment plan, used entirely for one's needs.
Of course, due to the "memory loss from drinking the potion," I couldn't verify this for the time being.
As for why I drank the potion, Dorian actually explained it clearly—
Forgetting some related things is necessary; otherwise, it would affect the treatment's effectiveness.
When a person realizes they are in a dream, it can adversely affect the dream's stability and the feedback they receive.
As a professional Master of the Dream Realm, similar experiences had been summarized before.
