Board Thread:General Discussion/@comment-35615238-20190716172252/@comment-32182236-20190723005809

...Perhaps it's because Asriel himself encourages this line of thinking.

Asriel flat-out tells us that when he turns back, we shouldn't think of him as "him". That we should remember Asriel as just a friend we knew for a little while.

Asriel himself wants us to think of Asriel and Flowey as two separate entities. Because he fears that he'll turn evil again.