Hi, I am wondering if anyone has any creative Ideas on how to fill this space.

I recently put in a new bath/shower in a basement bathroom, and my contractor/plumber told me that the toilet had to be 16" rough in from the wall, since he had to add a T connector to connect the plumbing from the shower to the same drain pipe. The issue is that you can't buy a 16" rough toilet, so I end up with a 4 in space behind the toilet.