Miku knew it wasn't a dream.
(It was more of a nightmare.)
The pain she felt when she first realized it was too much to bear. So she didn't.
The people she met on the street were nice. They had genuine smiles. They had no evil intentions whatsoever. They were just smiling because they were happy.
(But she knew that wasn't true.)
(Why did they smile? Why did they smile so warmly when the world they lived in was so cold? Why were they the only ones who smiled?)
Miku would imitate their smile (but she questioned their motives.) She knew it didn't really matter—knowing their agenda wouldn't change their conceited nature.
(But…would it hurt to pretend?)