Sure, it is clear that the
creature in your dreams, your 'dream person' is controlling and subduing your tadpole and perhaps your own resistance to it. They are clearly a magic wielding being since they state they have been looking for you. the Tadpole clearly does not need to look for you, it knows where you are. Also the Dream Person dreams of conquest and power, with you as their weapon to make it all happen. While Mindflayers do hunger for power, it is unlikely a newborn one would be as manipulative as the dream person is. The dream person is clearly a being with some degree of seducing ability, as it knows how far to push Tav in order to insure compliance.
My bet is is it some sorcerer, hag, lich, or other being that is remotely controlling you. Since there is a hag theme already, I was going with NightHag. But there doesn't seem to be any penalty to the dreams so that rules that out. My current feeling is it is a Netherese sorcerer or perhaps a Minion of the Absolute
I personally like the dream character a lot, so it is my hope we can somehow turn the tables on them.
