One of my favorite experiences is one that happened with my cousin. We are about the same age (she is eight months older; we were fourteen at the time). We were in her room one morning. Both of us were still in pyjamas. We were sitting on the floor, just talking.
I noticed she was eyeing my crotch, so I looked down. I was wearing only a long t-shirt and underwear, and one of my hairy nuts was peeking out a bit! I looked back up at her, she turned red and looked away.
I laughed and said 'It's OK...look if you want to.' I then pulled my underwear halfway down my thighs, giving her a good look at my balls and stiffening cock. She laughed a little, and stared intently. I asked her if she'd ever touched a boy there before, she said no. I asked if she wanted to, she giggled nervously and nodded a bit.
She reached out and grasped my balls. Her hand was so soft and warm. My cock instantly sprung to a full hardon. She continued playing with my nuts for a bit before moving to my cock.
I still remember how she cautiously explored the shaft with her fingertips. The way she pinched and squeezed the head. She was obviously enjoying it! I asked to touch her and she quickly complied. She slid her sweats down to her knees. Her pussy was so warm. She giggled a bit when I rubbed it. I put a finger between her lips and felt her juicy hole. She got quiet and closed her eyes. We felt each other for a bit, it was heavenly. We would've gone like that all day but we feared getting caught. So after a few glorious minutes we covered up and went about the day as if nothing had happened.