Well! It's certainly...joyful, if rather gross at the same time. Nevertheless, the mouse does not look wet, so there may not be any coffee (or tea, or whatever) inside the cup after all. Whew!
Oh yes, Wensley certainly looks like the type. Since the whole scene is also a bit weird, Mr. Hamstervic might be inclined to give it a shot as well ("and then 'CRASH!' you throw me and the big ol' cup at the floor screaming! And you need to have a big joyful grin on your face!")
I wouldn't mind this reference making a cameo appearance at the strip.
Wensley could sing it in a cup-cum-bathtub.
The word "wizard" is said to originate from the ancient "wyz-ars", literally "someone who, at bottom, is very smart."