Me: I think you need to find a new nickname for me.
Him: What do you mean, booger head?
Me: Exactly that - booger head is not a sign of affection. No one who overhears you saying it would think that it is.
Him: Why did you wait so many years to tell me that, booger head?
** Two days later **
Him: I think I'm going to call you "my sunflower."
Me: That's very sweet. I like it.
Him: But keep in mind that you have to pick a booger head, but a sunflower's just a weed.