They obviously became one. Remember the evil Tasara saying how he has a way to prevent the real Tasara from bringing about disaster and becoming a monster? It was along the lines of saying like he knows a way and he will do it but he might forget who Nara is. Regardless of that, evil Tasara is willing to do it in order to keep Nara safe. In conclusion, for now it looks like they have successfully merged as one different person and the result of that is forgetting.
I wouldn't mind this having 1000000 chapters.
Bestie same