Halloween Costume Sneak Peak

We are making me a Halloween costume and Rachel is teaching me to sew. Since the clock is ticking now this sort of translates into Rachel-does-all-the-hard-stuff-and-I-pin-fabric-togeter (and sew on patches). But I did manage to use the sewing machine to make a seam in one of the sleeves tonight!

Below is a partially assembled version of the costume. I'm not telling what it is yet, but I dare you to guess...