When I was about 15 I was standing in my room, looking out the window with my hands down my pants, fingering my asshole. All of the sudden my mother barged into the room.

I yanked my hand out. She marched up to me, grabbed my hand and held it to her nose.

"Your hand smells dirty!" she said, and then walked out.

I started fingering my asshole again, only now I had a hard-on too.