A variation on the spelling of the name Kristen. Chicks with the name Krystyn are typically unusually sexy. They usually feature modest sized titties, and have abnormally phat asses for their size. They are usually Petite women never exceeding 5'4".
Guy 1: Damn! Who is that abnormally sexy girl over there?!
Guy 2: Thats Krystyn.
Guy 1: She is God's gift to men.