That's to say, once inside the body it breaks down pretty quickly. And that affects how frequently people smoke. You take a big breath of cigarette smoke, the nicotine zips from lungs into bloodstream and goes to the brain where it locks into special receptor sites. If someone who smokes goes to a gym to exercise they like a cigarette after a workout. The reason is that exercising makes you metabolise nicotine faster.
Romance has nothing to do with it.
One cigarette may contain 1.2 milligrams of nicotine. It's been claimed that this amount could kill 7 adults if it was injected. However when you smoke you get an incredibly diluted dose. Most of it literally goes up in smoke. What nicotine remains in the lungs is in 5 or 7 litres of air.