Came to a Slightly Weird World

During a trip with his family, the male protagonist seemed to have been lost for two months. When he had memories again, it seemed that the world had become strange, including an umbrella floating out of thin air; an aunt who was obsessed with counting millet; a cat owner who refused to eat or drink; an empty concert; and a completely different class schedule from what he remembered. It seems like it's all trivial, but it's scary to think about it carefully. It seems that everything can be explained, but it seems that there is no way to explain it. The male protagonist wonders who has not changed. Could it be that they have all turned into fake people? I don't know, I don't know anything yet. Maybe there will be answers soon, or maybe the world has just gone crazy… This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.