The first one is obvious... to add the cat head 
to the choker.  Looks cuter.  Maybe the original 
artist forgot it, or it was an addition after a 
review.

The second one looks to be a correction layer to 
the edge Lina's sleeve and the top of her arm. In 
the the 2nd photo, they have offset the two 
layers to show the correction layer seperately.

Mistakes happen, even in hanken.