The Ocean near Hogwarts was a place Theodore liked. He could smoke without anyone bothering.

Another night, he was sitting there again. He had a cigarette in his hand, thinking about the classes, and problems.

Theodore‘s eyes narrowed as he saw something in the distance. He heard splashing, and a voice singing. He looked around, panicked, until he saw it again.

A fin. There was a Siren in the Water.