Peter felt a warm rush as the charm settled over him - it was admittedly a lot better than any he could do himself - and glanced up gratefully at whoever had cast it. When he saw the perpetrator he half yelled and tried to scramble backwards, but there was nowhere to go but back to the sea, and in any case he only fell up to his wrists in sludgy sand and seaweed.
Bloody Dumbledore. Of all the people. Possibly only Sirius would have been worse. "F-fine," he stammered, less out of cold than of sheer terror.