stink lines
n. In an illustration or cartoon, the wavy lines that appear over an object to indicate that it smells bad; the metaphorical stench emanating from something that is extremely bad.
Also Seen As
American Splendor is worth seeing, even if you've never heard of Harvey Pekar or the comic books that made him a cult figure a quarter-century ago. The low-budget bio-pic is a great story told with imagination and a sense of humor, but not reverence.

It presents several distinct versions of an odd guy who succeeded because of and despite of himself: the actual Harvey, shown in footage being treated like a rube by David Letterman and in the present; actor Paul Giamatti's dead-on screen portrayal during the heyday of Pekar's American Splendor comics in the 1970s and '80s; and multiple artists' renditions of him, including the caricature by Robert Crumb that Pekar's third wife, Joyce Brabner, described as 'a hairy ape' emanating 'wavy stink lines.'
—Terry Morris, “You'll enjoy getting to know Harvey,” Dayton Daily News, September 12, 2003
The comic strip where "Super Dom" saves the world from a hideous monster has a building-toppling "Burp!", an awesome "Bam!", gross "stink lines" and everything a 10-year-old boy could want in a comic strip.

That's because soon-to-be fifth-grader Dominic Griffin of Hampshire drew them there.
—Burt Constable, “Super Dom may only be 10, but he already has heroic ambitions,” Chicago Daily Herald, July 05, 2003
1995 (earliest)
They love anything smelly and three-dimensional. Why, you can practically see the stink lines coming off it. Look, I could stand here till I'm pink in the face trying to explain the joys of a good old-fashioned pile of stenchy things, but it wouldn't make any more sense to you than your toys make to me.
—Kerry P. Talbott, “The light before Christmas,” Richmond Times Dispatch, December 24, 1995
No matter how bad a movie is, the star is usually seen — and, often, contractually obligated to appear — on late-night talk-shows. Pluto Nash star Eddie Murphy, however, was AWOL from Jay Leno and David Letterman last week. Heck, even Matthew Perry, whose release Serving Sara has the stinklines coming from its own advertising, plopped himself down on Jay's couch last week.
—Sean P. Means, “Warning signs,” The Augusta Chronicle, August 27, 2002