Seonwoo is actually from this dimension (where Jehee is). He just switched bodies with the one who lives in that other dimension (where he play games). So it's basically Seonwoo just returned to his original dimension. He just lost his memories, but Jehee knows him since before, and he returns/regress so he could see Seonwoo again.
Seonwoo is actually from this dimension (where Jehee is). He just switched bodies with the one who lives in that other dimension (where he play games). So it's basically Seonwoo just returned to his original dimension. He just lost his memories, but Jehee knows him since before, and he returns/regress so he could see Seonwoo again.