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I'm a Mouse, Duh! Karen Smith Mean Girls Costume

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Product Information

Items Included
  • Bodysuit
  • Dress
  • Belt
  • Ears Headband
  • 97% polyester 3% spandex body suit 100% polyester dress
  • Step-in bodysuit has length-adjustable shoulder straps
  • Chiffon babydoll dress has ruffled, elasticized top edge, length-adjustable shoulder straps
  • Tie satin ribbon belt as desired
  • Mouse ears attached to faux-fur-covered plastic headband
  • Officially licensed, exclusive


You can't just ask someone why they're a mouse!  Well, that might be what the other Plastics think, but we think that Karen should be able to ask anything that she likes.  When you're the only nice one in a group of mean girls, there are a lot of things that you should be forgiven for!  Sure, the gal might seem a little ditzy, but that's only because she's so focused on developing her extra fifth sense for predicting the weather.  These are tough skills, folks!

Plus, who of the rest of the Plastic crowd are so capable of blending into any scenario?  With that delightfully open mind (admittedly partly because it is just a little empty), Karen is not only willing to accept all sorts of different people but can become so many things, too!  How many psychic, weather-forecasting, rich, highschooler mice-girls can there be out there!?  Karen Smith is clearly one in a million.  


Our team of designers faced all the fugly troubles of the high school cliques in order to put together this perfect (and officially licensed) Mean Girls costume featuring everyone's favorite Karen Smith's "I'm a Mouse!" costume!  (How meta is that!?)  This exclusive look includes a black one-piece bodysuit covered by a super-short, thin-strap chiffon baby doll dress with a shiny ribbon belt.  The mouse ear headband is wrapped in gray fur with pink satin for the inner ear.  Folks might think you're just a mouse, but when you quote Karen by saying, "I'm a mouse, duh," all will immediately recognize you for the best of the Plastics!


Become a little bit of everything in one look!  Be one part mouse, one part Mean Girl, one part weather reporter, a dose of psychic ditz, and total adorable package when you gear up with this exclusive Mousey Karen look from Mean Girls.  

Size Chart
X-Small Bodysuit Chest 28 1/2" 72cm
X-Small Bodysuit Waist 24" 61cm
X-Small Bodysuit Torso 22 1/2" 57cm
X-Small Dress Length 23" 58cm
Small Bodysuit Chest 30 1/2" 77cm
Small Bodysuit Waist 26" 66cm
Small Bodysuit Torso 23" 58cm
Small Dress Length 23" 58cm
Medium Bodysuit Chest 32 1/2" 83cm
Medium Bodysuit Waist 28" 71cm
Medium Bodysuit Torso 23" 58cm
Medium Dress Length 24" 61cm
Large Bodysuit Chest 35 1/2" 90cm
Large Bodysuit Waist 31" 79cm
Large Bodysuit Torso 24" 61cm
Large Dress Length 25" 64cm
X-Large Bodysuit Chest 37" 94cm
X-Large Bodysuit Waist 32" 81cm
X-Large Bodysuit Torso 24" 61cm
X-Large Dress Length 25" 64cm
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(4 Reviews)
    Five Stars
    By Zandalee | October 18, 2020
    Size X-Small
    Super cute! I had people recognize it from mean girls. It's also comfy.
    Bottom Line Yes, I would recommend this to a friend.
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    fits like a bag
    By Current Customer | October 21, 2020
    Height 4'10" | Weight 127 | Size Small
    This costume is awful - gives no shape and the ribbon doesn't even fit around the waist. The dress in the picture gives shape to the girl. I have curves and it looks like threw a bag on myself.
    Bottom Line No, I would not recommend this to a friend.
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    Five Stars
    By Anonymous | October 18, 2020
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    Would recommend
    By Drew | September 9, 2019
    Arrived earlier than expected, and is so comfortable it doesn't even feel like you're wearing a Halloween costume. It looks exactly like the picture except for the fact that it's a bit shorter which isn't a problem at all. I would definitely recommend ordering from here.
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