You were completely, utterly mistaken. As soon as you got the job, your perspective on Mettaton completely changed.
You assumed he’d be this cheerful robot that he appeared to be on stage, treating his employees with utmost respect and kindness for their service.
That was where you were also mistaken. He was pretty much the opposite of what you expected. What he actually was, was greedy, snooty and demanding. A total dickwad, if you will.
The only thing he made you do as his “assistant” was get him coffee, which somehow he was able to drink apparently? That and do miscellaneous chores that were totally ridiculous, like dust off all of the original copies of every single movie he starred in, or arranging his ties by glitter color.
In a strange way, you didn’t really mind doing things for him. You couldn’t put your finger on why.