

It’s not unreasonable. I wouldn’t work for this person, or I would accept work to do and then come back to them and say “I needed to prioritize better paying work, I can’t get this done on time.”
Like, do you think this person is treating you honestly in any measure? No. They are breaking the social contract. Don’t give them an inch.
Not really how that relationship is determined basically anywhere.
Piecemeal employment contracts exist, they are still employment relationships.