So basically seonwoo of the real world and the one in the game switched sides when they were 9. Which means the seonwoo that was during the whole story is originally from the game who went to the real world at 9yo and came back to the game later on switching with the other one. And during the end when he died and everything resets due to jehee's regression skill, he repeats the same thing that happened in the start of the manhwa (finding himself in the game and meeting jehee) while the seonwoo that lived 20 years in the game came back to his real world that he belonged to originally but got taken at 9, they also show the jehee of that universe being a ceo or whatever. I hope u understand if not ill find another way to explain it better

Bro I'm so confused by the ending can someone explain