Since the one who directs the theatre play looks like he knows something and big bro getti...

Since the one who directs the theatre play looks like he knows something and big bro getting angry,, theres a probability that this theatre play is the real story in the past. Ryan/past Jifeng has that red mark on his forehead, the same thing thats on Aoao's big bro right now. Maybe thats the thing they were looking for in earth currently.

In the past, aoao is indeed the black dragon (so yeah his big bro is ofcourse a dragon too), whilst ryan is a normal human being., now what happened is jifeng/past ryan got that powerful thing they were looking for and in turn get possessed by it. Hence he got the red markings and never let aoao/past xuan ye because he is possessed. Possessed by that super obssessive thing that makes them have that intense feeling to the person they like. Old jifeng to old xuan ye. past jifeng killed Xuan ye and obtained black dragon's power. and then here comes big bro to save past xuan ye but its too late. But bigbro in rage managed to kill past Jifeng. In turn, bigbro obtainesd that powerful thing, that red markings, and he does the same to grandpa/earthGod, being possessed by that thing. The reason he forget might be the one who erased aoao's childhood memory , (maybe he doesnt want to remember or forced because, hello evil). Its obvious in current time that bigbro likes grandpa/earthGod so his heart still remembers although he doesnt recall any actual thing. and , that red markings is still on Bigbro, so the thing they were looking in earth, might not be actually there.

Maybe the one who Xuan Ye curses before, is not Jifeng but the one who possesses him,, that red markings that they were looking for, seems like a conscious spirit/soul with enormous power.