The iPhone is a very well designed device, so why ruin it with a cheap plastic case? Instead, get something like the Wool & Leather iPhone 5 Sleeve by Cocones.

This minimal sleeve offers a 100% Merino wool felt construction with a tasteful leather strip down the center, adding both style and protection. The sleeveā€™s design is sure to fit into your hip wardrobe while still protecting your phone from keys or whatever else may be in your pocket.

You can grab a Wool & Leather sleeve for your iPhone 5 for $32.