I don't feel like I should paint at work.
Seriously? I hope your kidding. Why don't you want to paint at work?
I want to be successful in a different career.
It's understandable to not be invested in something you don't consider a part of your career path, but its wrong to shirk duties at a current job. You may end up getting disciplined or fired if you don't do your job.
I am steadfast to do my job - it's not in the job description to have to paint.
Oh wow, that's not cool for your employer to force you to do something outside of your job responsibilities. It feels like they are looking for slave labor. You should tell them no and why, so that they don't take advantage of you in the future.