All the same, the neck will change shape when it bends, and the choker will not. This is a problem with Poser, that at present although the body can affect the clothing, the clothing cannot affect the body.

If the choker is supposed to be hard and unyielding, then you either have to make it larger, or use a magnet to squeeze Vicki's neck.

If the choker can be elastic, then check "inherit bends of parent" when you parent it. This will avoid having to make a conforming figure - very useful for cases like this, were the prop covers only one body part.