My girlfriend (I'll call her Lori) has disciplined me in front of her sister (I'll call her Mary) on multiple occasions.
On one such occasion Mary's boyfriend (I'll call him Joe) was also present. I had forgotten that the four of us were having a BBQ at Joe and Mary's place on a Saturday afternoon, and I was supposed to bring the pork chops. I was supposed to be there by 3:30pm. When I hadn't arrived by 4pm, Lori called me on my cell phone. I was at a friend's house, helping him build a back porch and deck.
Of course, I apologized profusely. Lori sounded VERY understanding when she said not to worry about it, but to please go home to shower (I was sweaty from the outdoor carpentry), and to please show up at Mary's place ASAP. I was about 25 minutes from home, so it took me about 45 minutes to drive home and take my shower. Lori texted me, whiIe I was in the shower, to remind me not to forget the pork chops. Then she sent me a second text that just said, "I love you." (with a ? emoji).
I was thinking, while I was getting dressed, that Lori was being very understanding (because of how calm and forgiving she sounded on the phone and in her text messages). Joe and Mary lived only about a half-mile away, so I calculated that I was going to be about 1.5 hours late. I thought to myself that, even though Lori sounded very understanding, I would probably be punished when we arrived home from the BBQ.
In my rush to get to Joe's and Mary's place, I almost walked out of the house without the pork chops. When I went to retrieve the pork chops from the freezer, they were gone... in their place, in the freezer, was Lori's hairbrush and her penis whip! I was absolutely horrified when I came to the realization that Lori had already retrieved the pork chops and intended/expected me to bring the hairbrush and penis whip to Joe's and Mary's place! Lori had previously disciplined me in front of Mary, but only at our house, and never in front of Joe (in fact, never in front of any male). I knew I had no choice, so I walked the half-mile, carrying the implements with which I would be punished.
Lori, Joe, and Mary were in the backyard and had already eaten by the time I arrived at the BBQ. When Lori saw me arrive in the backyard, she said very calmly, "You'll be going to bed without dinner and with a VERY sore butt tonight."
"And Mary wants Joe to see how she plans to discipline him moving forward, so I'm going to punish you right here, right now."
"Give me my hairbrush and penis whip, and strip down to your boxers!"
"Yes ma'am."
"Just like at home, you're not allowed to have an erection while you're over my lap. If you do, I'll whip it until it's flaccid."
"Yes ma'am."
"I can see that you already have an erection. Take off your boxers!"
"Yes ma'am."
At this point, I knew what to do. I laid myself across Lori's lap, face up... with my butt on her thighs and my bare erection presented for discipline where you would usually expect to find a bare butt during an over-the-lap spanking... a very uncomfortable position! Lori began thrashing my erection with her penis whip. At first the thrashing only aroused me more -- I went from hard to rock hard. But, after about 5 minutes, I went flaccid.
"Okay. Turn over, so I can blister your bottom!"
"Yes ma'am."
At this point, Lori began with the hairbrush. My erection returned after about 5 minutes, so I had to turn back over for another penis thrashing. Then I had to turn back over again for the completion of my butt blistering.
Having this discipline administered in front of Joe and Mary, in their backyard, was one of the most humbling punishments that I've ever received.