Language misunderstanding…(?)

A few days ago I went into town to do some grocery shopping with two African men from the museum who do not speak much English. The three of us had to crowd into the front cab of a pick-up truck. One of the guys who is about my age sat in the drivers seat, and I tried to squeeze in the middle so that the other, much older gentleman would not be squished between us. As I was folding myself in he said, “I am small so I will sit in the middle.” “Ok,” I replied jokingly, “my bottom is too big.” He replied gravely, “Yes, I see.”