As dirty as he can get - in every sense of the word - Alex does enjoy being clean just as much, and always has, even in his younger years...he's not quite sure about the duck, though - oh well, it'll make a nice gift for Arthur Weasley in a few years.
, this time we have an unblemished Alex (since he didn't get the scars over his eyes until he was 18) getting himself all squeaky clean just before bed during weekly Bath Night, which happened to fall on a Full Moon this time, so he's in full puppy mode.
And yes, the title is a reference to THAT game - but screw dragons; werewolf washing is where the real money is.