For every average there is an exception. The question, what? It is filed under taboo incest, and runs about 1400 words. 2.7 out of 5 from 175 readers.

Others under taboo incest Older Sister's Embrace, My Lingerie-Loving Sister Moves In and 2 Moms, 2 Sons... Ch. 5, and 9 more.

Or keep going.