Quote by RichInMich
Not really walked in on them, but we did overhear houseguests having some fun one night in our house... There's nothing like the sound of another couple making love to get your own juices flowing - we had incredible sex ourselves, then!
While parking, I watched in the rear view mirror as the couple we doubled with fucked while my date gave me a blow job.
One time. Traveling on business to the Hampton Roads, Virginia area. Checked into hotel in mid-afternoon (multi-floor hotel had outdoor, balcony-like walkways in front of each room), used my key (it was in the 80s when keys were often metal keys not a card), opened the door and two folks were going at it with gusto. I stopped, stared for a moment, then closed the door and retreated quickly -- I realized I might have walked in on something not Kosher (it was midday) and they might have reacted ugly, possibly with a gun.
I returned to the front desk, asked for another room, telling the clerk the one he had given me appeared to be occupied.