You and your wife are in a relationship with traditional gender roles. It's something you've both value, and a commitment you've made to each other. That's not going to change just because your wife wakes up one day to find that she's grown her very own PENIS overnight! She is very nervous at first when she shows you, making you reaffirm your commitment to your traditional relationship before she reveals her new genital configuration. Comparing it to your cock, she realizes that her penis is significantly bigger than your own. She speculates that God must have seen fit to give her a cock because yours is too small, so God wants her to be the man in the relationship. That must mean that it is His design for you to become the woman. She is now the husband and you are the wife. For her first act as your husband, she orders you to get down on your knees and suck her off, reminding you that the wife is to joyfully obey the husband's orders. You do as you are told, but your now-husband isn't done with you yet. In order to fulfil God's plans for your family, she must breed your pussy. Unfortunately, God did not see fit to give you a pussy the way he gave her a cock, so the two of you must improvise. She decides that your ass will be a serviceable hole, and commands you to spread it. She fucks you hard and breeds your ass-pussy while sweetly and cheerfully reminding you of all the things you used to tell her about a wife's duties, your own words coming back to haunt you now that you are the trad wife in this relationship.