There is a city in everyone's heart. Every city has a gate. Every day, people come and go through this city gate. Some of them are permanent residents, sitting in this city from sunrise to sunset, crying and laughing. Some of them only stayed for a short time. For some reason or by accident, they came here and left here again.
In each city, there will be a lord of the city. He is aloof and unshakable. Unlike other kings in real society, he is immortal until the city collapses.
Both the heroine and the hero are non-novices