My pregnant sister asked me to "just do it once," so I promised her I wouldn't tell anyone, and that's how I ended up having sex with her. (NHDTA-270)

The younger brother, who fantasizes about his older sister but has always suppressed his desires with reason, can't help but reach for her body after learning she's pregnant. Confused and unable to resist, the older sister begins masturbating and performing oral sex. Unexpectedly, the excited younger brother's demands become increasingly outrageous, even going so far as to suggest intercourse...