Marmaduke is cheating on his girlfriend.

Marmaduke stole all his neighbor's newspapers and brought them to his owner-man. If you're wondering why Marmaduke thinks bringing Owner-Man dozens of copies of the same day's newspaper is a nice thing to do for him, rather than something that would just piss him off, you obviously haven't once paid attention to a word I've said.

Marmaduke is trying to use belligerent anger to convince an automobile to do what he wants.

Marmaduke creator Brad Anderson, eternally ten to forty years behind the curve of popular culture, has confused "looking younger" with "looking like a douche."

Marmaduke stole some skis and broke his leg. The entire situation utterly baffles his owner-man.