What is this utensil for? My sister inherited a bunch of tupperware and plastic utensils. One of them, we couldn't understand its purpose.

 
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Ideas so far is to keep pizza-box lid from falling, or to measure equidistance for slices in a cake. What is the name and purpose of this utensil?
My google-fu powers tell me that yes, it's indeed a mini cake divider.

You put it on top of the cake and slice through the slits to get uniformly sized cake slices.