In the game あつまれどうぶつの森, フータ the owl's job is to evaluate fossils that the player brings him. If you bring him a fossil that's already in the collection, he will say that if he had enough money he would buy it from you:
Well, that's just an impossible dream.
Anyway, let me return this to you for now.
My question is: what kind of affectation is 〜ますです? In what speech register would it even be appropriate? If it is appropriate in some speech register, who typically speaks like this?