"Unreasonable demands" refers to requests or expectations that are not fair or rational. These demands are often difficult or impossible to meet due to their excessive nature, lack of reason, or unfairness. Full definition
You might feel under pressure because you have too much to do, too much on your mind or other people making unreasonable demands on you. (grandparentsplus.org.uk)
The search for the legislative intention in the context of criminal justice legislation makes unreasonable demands on the intellectual efforts of judges and lawyers. (slaw.ca)
What unreasonable demands for this customer do I have to satisfy? (angryretailbanker.com)