There are many universes, you are you, she is you, and every choice you make without a choice may be chosen in another parallel world.
Mu Qing was exiled to Earth due to poor supervision. Many systems escaped because the gate of time and space was found and destroyed.
Mu Qing was pulled into the dungeon as an NPC by the system but accidentally awakened as a player. She was kicked out the second after completing the task and returning to the infinite world because she was bound to a second system.
Purpose: Courage and friendship grow