Seven Days in the Ruined City: A Solar-Terms Mystery

The protagonist accidentally enters the "Seven-Day Ruined City," an abandoned ancient city shrouded in dense fog where time has stopped. Here, "seven days" form one cycle. At midnight on the seventh day, anyone who has not collected all "Twenty-Four Solar Term Seals" is erased by the city's "Mist Shadows." At dawn on the eighth day, they lose all their memories, come back to life, and fall into an endless loop.

Time stands still outside the ruined city, while it flows normally within. The city is filled with dilapidated old houses and deserted streets, as well as "natives" driven mad after being eroded by the "Mist Shadows." They are participants from previous cycles who failed to escape and lost their sense of self. The central metaphor: the ruined city is an abandoned site of ancient solar-term rites, the participants are "sacrifices," the loop is an unfinished ritual, and the solar-term seals are the key to breaking it.