A glove fits on the hand perfectly (or should). So you're saying something fits in perfectly, the way a glove would fit on your hand. Though it's normally used for clothing, Viero's "Ace Ventura" quote is another great example. :)

I agree with Caprisun, that the skirt was the exact size for you, wasn't neighter tight nor loose. (Jim Carey used the same expression in his hilarious movie "Ace Ventura" when he parked his car, saying: "like a glove!". that means he parked exactly as he wanted).

The skirt was the correct size for you.