You're starting to feel a little light headed, and you guess it's because of the costume, so you try to take it off, but the zipper is stuck. After a few minutes of tugging at it, your dizziness gets worse and worse.
You stumble a little and decide it's gone on long enough - time to call in the paramedics.
The last thing you remember is stumbling toward the phone.
Waking up, you find yourself in your room, naked, with no costume. You look around, and find the packaging and receipt, but the costume itself is completely gone.
"What the... did someone come in here and steal it?" You start looking through the apartment.