What is a smoking fetish?
Smoking fetishism (capnolagnia) is a sexual fetish, where the person is sexually stimulated and fascinated by watching others smoking of tobacco - including cigarettes, cigars or even pipes. It is thought that most smoking fetishists are heterosexual men, though there are small groups of homosexual and bisexual women who have expressed similar interests in the fetish.
The smoking fetish appears to be rare enough - enough so that its existence went fairly unnoticed until the dawn of the Internet, when fetishists began to meet online, trade pictures of smoking women, short stories, and reporting sightings or simply discussing their fascination on open forums. Some of the earlier news groups were alt.smokers.glamour (ASG) and alt.sex.fetish.smokers (ASFS).
Some, but not all fetishists have a fascination with the addictive properties of nicotine, and its ability to cause harm, and there is a sub-fetish relating to women being harmed by smoking, sometimes called "the dark side" or "lung damage". This may suggest an element of misogyny in the community's psychology. A large number of fetishists are also known to have a strong attraction to the glamourous aspect of smoking by women. Historically considered a masculine habit, the feminization of smoking with the advent of fashion brands specifically marketed towards women has drawn the attention of fetishest who see the use of these brands as a way for women to increase or enhance their sexual appeal. Most often this fascination is focused on young fashion-conscious professional women who are the target demographic for these brands, which are differentiated by slimness and added length over traditional brands of cigarettes.

The increasing intensity of anti-smoking campaigns, moreover, turns smoking into a transgressive and taboo act; eroticized images of women smoking may take some of their power from depicting a taboo being broken. Another cultural source for the fetish may be eroticized depictions of women who smoke that come from older motion pictures, especially from the film noir era.
The smoking fetish has emerged in recent years as one of the more socially un-acceptable fetishes, likely due to the rising social unacceptability of smoking itself in western cultures. For this reason, fetishists are often reluctant to admit to their fetish, and so its prevalence in society cannot be accurately estimated.