I've arrived on earth from a far-away galaxy. My mission is to harvest sperm because the males where I'm from have become infertile. John is very surprised when I appear in his house, but he's happy to help me with my mission. Things are done very differently on my planet (sperm is mechanically extracted and kept in containers). What is sex? John offers to teach me. Unfortunately, the sperm didn't get harvested (it ended up inside me!) Never mind, we'll just have to do it again!