When I was seventeen, my dad wanted me to take wrestling lessons. I took the wrestling lessons from his 26-year-old buddy who was a wrestling coach. I was scared I would get a hardon. As we got into it we both got hardons and with all the rubbing of our crotches we both ejaculated our cum.
Fortunately we were wrestling alone with dark brown suits and the wetness didn't show. We relaxed a bit and wrestled again and then we orgasmed again. We didn't say anything about it to each other.
When we took our shower we were still hard and we jacked off each other. That was the first time for me, but I don't think it was for him. He was good looking, athletic and had a near eight inch cut cock. I took lessons from him all summer and our hardons subsided somewhat, but we still mutually jerked off each other in the shower for the summer, when I took lessons from him. I personally think dad knew what would happen and it did. I was happy about it all.