Your step-sister has to ask a huge favor of you. Her and her boyfriend broke up but she needs your seed to get pregnant. You tell her how crazy of an idea that is, considering you two are step-brother and step-sister. She starts guilting you for all the things she has done for you over the years and how now that she needs you, you are really going to give her a hard time? "I don't have time to date someone to see if they will get me pregnant!" "It's going to take too long!"