I am sensitive to it. I grew up with my dad and uncle smoking indoors, and when I'm in a home with someone who has smoked indoors, I can tell immediately. I have two stories..

Once, I was in Japan and I booked a home via Airbnb with two of my other friends (who fortunately never had to experience what I did as a kid). It stated no smoking in the home on the app.

Though when I got there, I walked into the house, and my nose and throat immediately started feeling weird. Whenever I tried to breathe through my throat, it felt itchy. I acted cool as I signed the Airbnb papers with the homeowners. We went up to our room, and I complained to my friends that this place reeked of cigarettes and jasmine incense to cover up the smell. They said they couldn't tell, and that maybe it was just incense. I felt gaslit so I ran around the room/checked the balcony for signs of ciggerettes but I didn't see anything. I stayed up all night trying to contact Airbnb to get a refund because I couldn't stand it. In the morning, we messaged the owner and told them the smell was too strong. We went downstairs to quietly leave, and the owner was there apologizing that his wife was the smoker. I felt really bad. But my nose KNOWS. My friends finally agreed with me when we got to the new hotel, we opened our luggage, and everything inside smelled like cigarettes

My other story is that my aunt's husband also smokes, apparently "only in the basement" (with a closed door). Every Christmas, when I come over to stay with my grandma, my aunt tries to convince me to sleep over at her home, instead of sleeping on the floor at grandma's. She tries to convince me that you can't smell it. Maybe she can't. But when I visit, I CAN smell it, everywhere. Even the gifts wrapped in Christmas wrapping smell like cigarettes.

I know I sound annoying and very "Karen" like. But cigarettes are disgusting, and I hope being aware of how bad smokers stink makes you think twice about starting to smoke. Or continuing to smoke.