Wearing panties in front of girls
When I was 14 I got chatting with a girl called Becky on IRC when I let slip that I sometimes wear panties. She laughed and said she sometimes makes her little brother do that. She asked me if I was wearing panties right now, I said no, and she said "then put them on, NOW!".
I was a bit embarrassed so I stalled, and asked what color they should be. "Pink!" she immediately replied, "and hurry up!". I went to my sister's drawer and found a pair of her pink panties with cute little flowers all over them, took all my clothes off and put the panties on. As always, I got instantly hard.
I told her I'd done what she said, and she replied "now you have to show me!". She gave me her Skype and told me to call her. When I did I was surprised to see 3 girls there, all a few years younger than me. "This is Beth, and this is Ashley" Becky said. Beth waved her hand and said "Hi, girlyboy!". All three of them laughed.
"Show us your panties!" ordered little Becky. I adjusted the camera so that they could see the very girly pink panties I was wearing. "Awww they're so cute!" said Ashley. I blushed. Then Beth, who seemed a little worldlier than the other two, told me to take my thing out and rub it.
It was very naughty and embarrassing to do this in front of the girls but I did as I was told. "Look, it's all big!" said Ashley. "That's because he likes wearing girl's panties, isn't it?" replied Beth. I nodded and she laughed, adding "silly little panty boy."
All the laughing and teasing was getting too much and within a minute I was shooting hard, coming all over my little sister's panties. All three girls clapped, laughing hysterically. They had never seen a boy do that before.
When Becky had recovered she told me how funny it was to see me coming in my little girl panties, and would I call her again? I said I would. I did call Becky a few times after that; she would call me "panty boy" or "sissy" and "order" me to wear panties, bras and nighties and laugh at me, but nothing beat the intensity of that first time.