I went to my girlfriend's house to stay over with her family's approval. She and her sister share the same room with a bunk bed. But I couldn't calm down, so I asked my girlfriend to have sex quietly without her sister on the top bunk noticing. As I was thrusting without making any creaking noises... surprisingly, the sister who should have been on top was peeking from my girlfriend's blind spot! And she was beckoning me over... My girlfriend didn't notice a thing with slow thrusts, so I winked at her sister and finished inside her! Then I slipped into her sister's futon for quiet sex. A dream come true—two rounds of in-and-out action with sisters in one night!
