A Katie is physically stunning at all times, from the moment she wakes up and the moment she falls asleep, even throughout her dreams.
They are usually funny and very modest. Also very cuddly, and extremely fuckable. Not to mention sweet, and caring.
You'd be lucky to ever have a Katie in your life.
Daron: "Oh, yeah. Katie, isn't it?"
Person 2: I know her, shes amazing! Her boyfriend is so lucky!