When Razz's parents decided to move away from Crust Town, it was a no-contest decision that Razz wasn't mature enough to take care of herself. Thus, her family hired an inventor to construct Vinegar, a golem made to look after not so little Razz. Unfortunately, Vinegar was brought to life before she was completed, and as a result, her body is upside-down, which is thought to be the reason for her apparent slouch and grouchy personality. The wheel on her back is meant to both counter her top-heaviness and allow her to move about easier, as her "feet" aren't actually feet.
She may sound cold and grouchy, but Vinegar cares deeply about her duty and her lazy, unambitious charge, even though at times it doesn't seem so. Vinegar often scolds Razz for not being very lady-like, particularly the way she sits.