Are both sentences OK?
There is nobody here that fits that description.
There is nobody that are staying here that fits that description.

Question

Answer

The first sentence:
There is nobody here who fits that description.

As for the second, I would rephrase it to:
There is nobody staying here who fits that description.

Answer

The first sentence is the correct one Sinem.

Answer

I don't think anyone would use that second sentence ever!:)