I remember i really haven't explained why i have both of them.

So here we are now!!!

*ahem* Once I/Frisk knew that Flowey was actually Asriel, I told Gaster about it. (much to flowey's demise) He started working on a way to split both of them because.... well..... I don't know. That part's still a mystery to me too.

And he didn't even show me how he did it rather sooooo.... yeah.