Wonderful Flipped World

What would happen if the world were turned around? Liu Yuan's head started to have wild thoughts again, please don't panic, he often has brain cramps like this. "Ding dong" Liu Yuan's doorbell rang. "Please sign for your express delivery!" Liu Yuan was happy, thinking that some fool had misremembered the courier, and when he opened the courier, he received an admission ticket. That's right, it's the ticket to the world he imagined. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.