Just waltzing around

Alex sighed as he wandered around the clock tower courtyard, thinking hard about how much trouble he would get in if he managed to pull off a prank in the Prefect's bathroom. It occurred to him that if he let anyone know about his plans then he could already be in deep, deep, dragon dung. Which was very unfortunate, as just yesterday he had blabbed his mouth off to anyone that would listen in the Hufflepuff common room. This would put him back a couple of days because he would have to think of another place to do it if everyone knew it was in the Prefect Bathroom. So as the sun glinted down on him Alex began thinking, thinking so hard, that he did not notice anything around him...