Hmph. This is a tough one. I'm really not too much OCD about anything. I had to ask Jon for what he would say I'm OCD about and he immediately said "your hands!".
I chuckled inside because I don't realize how I am sometimes about them. I wash my hands like 8,000 times a day. When I'm at work where we don't have a bathroom, I am constantly using the hand sanitizer. My hands are so dry because of this.
I also am super OCD about my nails. I am a nail biter. I've learned that if my nails are perfectly painted with no bubbles or imperfections, I don't bite them. So, I literally paint my nails like every other day.
Here's a picture when I painted them leopard... :)