"Object Person" = a human being who can turn into an object
The time period when you become an object is called the "current period", and the time period when you become a human being is called the "human period".
Every ten years, the object person can have the opportunity to replace the "object that will change".
Shadow-catchers are extremely rare, so the price of shadow-catchers on the black market is extremely high. Those governments and non-governmental organizations that specialize in capturing shadow-catchers are called shadow hunters.
John Watson was a thing, and a rare breed at that—an old-fashioned single-cooling window unit. He is being rounded up and Sherlock saves him.
But is it really like "I was just passing by" as Sherlock said?
Fuhua, ooc, AU, maybe cheating, maybe NC17, a sudden memes on Weibo, post it to give yourself some motivation orz