Field removed from entry layout is still displaying
I figured it out. The problem was that the code that set seoAuthor on every template was still there. So even tho the field was removed from the layout, the db still contains that field, so is able to retrieve it. 

The fix was to remove the code that set the variable in the templates, and now works as intended. 

One thing that still confuses me is why craft still pulls the data if is not in the layout anymore.