kiss of death

:  something (such as an act or association) ultimately causing ruin The movie has a G rating, which is almost a kiss of death. Last year, fewer than 2% of new films were rated G, and nearly all of those were animated. — Sports Illustrated —usually used with the Not long ago, when I proposed to my agent that she champion a book of mine as a work of literature instead of trying to present it as a “Sixties memoir,” she told me, with a rueful laugh, that in publishing circles nowadays the “L” word is the kiss of death. — Joel Agee … a faraway region whose populations are so deeply anti-Western that any government cooperation with America can be the kiss of death … — Alan Tonelson