Rabies was Milo's dog, who could talk. He only appeared during the first few years of the strip, later to disappear at about the same time that Opus became a regular character. Most of his final appearances were simply as part of the Sunday edition, specifically leaning against the logo while smoking a cigar.
Rabies was also a character in Breathed's previous comic strip, The Academia Waltz, where he was Steve Dallas's dog.
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