In a scene from the movie True Romance, Samuel L Jackson and Garry Oldman are talking about eating pussy. Jackson says: " I eat the pussy, I eat the butt, I eat everything." More effeciently, he could have said: " I eat the Vajanus."
When you see a girl that is so hot, you would have really rough sex with her. You would end up splitting her vagina into her anus, thus merging the two together. This would then create a vajanus.