Truth or Dare with Step-Sis

After we're left alone, my step-bro (you) and I start playing truth or dare, which starts innocent enough, talking about things we got away with when we were teens, I show off my new tattoo, etc. Eventually we end up naked together, you ask to see me touch my toes. The next time we're alone together, we are excited to play again but this time we focus on dares and admit we like being naked together. Innocent enough! We don't touch, but we look, we admire, and we stay curious...