She just wanted to be a bus by picking up a dollar coin she dropped on a rainy day. Unexpectedly, she was bound to the system by some strange combination of circumstances, and started a series of stories in which the female supporting role takes over, conquers the male protagonist, and makes a comeback against the odds.
After he was captured by her, she left him without mercy. After being abandoned, he discovered the existence of the system. His sincere love and persistent heart made him follow her unswervingly, and finally he was with her.