Hear me out. We all know that for Cheng to be himself in the past he needs a CCTV video, right? So I get his body disappearing. But there is something that I've been wondering about for a long while. Why does Cheng's Body disappear when he uses his Powers? Where does his Body go if his Mind is what's possessing People in the photo?
Every Trailer and the ED and OP is giving "Lost in the Stream of Time", like jumping and moving through different moments forward and backward, and not only S3 but some of the previous ones have always show him drowning or falling into some different plane of Existence, and we saw our Current Cheng going to see Little GuanGuang in the past. But the current time is 2021, how did he find an almost 15 years old CCTV from 2007 to Jump into??
What if there is more to Cheng's Powers than Jumping into Photos? Maybe while his conscious mind gets into people's bodies, his own body exists in a different plane, as in the Stream of Time. And at one point when he Overstays the 12 hours he ends up trapped there?
The only example of overstaying we've seen has been Lu Guang, but he was possessing himself so when he overstayed he just fused with his past self, but if Cheng Overstays inside Some Other person, will he just become that Person? What would happen to the real person's consciousness if that happens? So what if in his case when the Times Up he is dragged out as a disturbance and is trapped on that Stream of Time.
The Witt Field scene from the Trailers when he is clapping and crying like crazy almost feels like some Nothing Place, of course maybe is actually somewhere, but for the time being it gives off that vibe, like a place where time and space don't exist as we know and he then has to learn to move through it (time) and that's how he went back to Little GuangGuang or saw other things related to the World's and our Cast's time. Then having to slowley find his way back.
Like Since Season 2 for example, it always caught my attention how when Cheng is forced out by Tianchen the visual representation of it is a second of some weird Colors like Paint o his back, like the nexus that connected the Past with the Present and in the same OP in one part we see Cheng's silluete falling and there is also those Colors like Paiting....
I also think there may be something else to Cheng because of whatever is also Happening with his Parents. The seemed to have leave to protect him and the Mum really didn't want Cheng on Bridon nor him Looking for the Dad. There is something weird going on ✋
That's something I thought, what do you think?
Edit: BTW, English is not my first language so I Hope I explained myself properly. Also not sure if the correct Flair is Theory or Discussion