If the Panties Fit

I gave my friend a few boxtops for education to take to school.  I had trimmed all of them except one.  She said that was all right, she didn't trim hers; it was enough trouble to check the expiration date.
I said that I trimmed them and checked the expiration date as the students turned them in.
She said, "That's very...."
"Anal," I offered.
She said, "I was going to say thorough.  I was, I was going to say thorough."
I said, "But if the panties fit?"