Because she tweeted out some Florence + The Machine lyrics?
People just like to fantasy book Sister Abigail and will look for anything to back it up.
There are several things both that she has tweeted and some things happening during the Firefly Fun House segments that is teasing this to be the case. There has been a woman's laugh during segments recently that sounds like Liv and Bray also hung a picture up on his wall where all his "friends" are that was a solid black picture. About the same time she changed her Twitter picture to a solid black pic. Those are just a couple of things that some people have picked up on.
I haven't watched last nights episode and didn't realize she was drafted to Raw. That was just what I was reading in some post over the weekend but I guess they were wrong.