Damn. I was hoping this wasn't inspired by Questionable Content. Then I could use the "Happy Birthday Grandma!" line.
Well the only way I could see this getting worse: "Happy Birthday Grandpa!"
Or perhaps: "Wow, you're way better than Mom." (Think about who'd you say that to...)
"Wait, you put in on before sex?"
"Oh, so that's why they're called STDs."
"Man, doing it with someone alive is much more enjoyable."
"Wait, you're a chick?"
"Oh MOM!" (While it not being you're mom.)
"Now that I'm done with rape, I can move on to murder."