It toyed at his mind, distracting his thoughts, playing with his memory. He couldn't recall it having been there, yet he knew that surely he must've seen it. True, he was typically distracted with other areas when it would've been visible, but he was a rather attentive man. He should've noticed it. Hermione Granger laughed with her friends, enjoying the warm summer air. She never noticed her professor, friend, lover, eyeing where denim met skin. Shorts having ridden up, a birth mark in the shape of an S was just visible. He smiled at his discovery.