In a world so often fetid and unfriendly, thank heavens Valentine's Day soon will flaunt the bond between the heart and the nose.
If you've never considered the connection, consult with cognitive neuroscientist Johan Lundström, who makes his money by studying how mating calls can be smelled as well as heard.
— From What love smells like: Scientist speaks on 'Nasal Attraction' at Philly.com.
I read somewhere that the thinking is that part of what makes kissing pleasurable is smelling the other person. Apparently it becomes somewhat less enjoyable to a person who has a diminished sense of smell.
How interesting, I never thought about that.