This all happened the other day when I was sleeping over. I am 185cm tall and fairly muscular, and my friend Matt is about that too. We had just been down to the park to kick the football and we were hot and sweaty. We decided to have a shower and get changed. He got in first and when he had finished he had his towel around him and he invited me in. We haven't seen each other naked but we have seen each other with boxers on.
After I had my shower and was getting changed, I had just got my boxer briefs on when he opened the door. He was asking what I wanted for lunch but he kept looking at my crotch. I told him and he left.
Later on when we were sitting in his room listening to music and talking he asked me how big my cock was. I told him it was 19cm and fairly thick. He didn't believe me so he asked to see it. I took off my pants and it was floppy at about 14cm.
He then grabbed it and it went immediately hard and it was huge he said. He then started rubbing himself and me. Eventually I came all over him while he came in his pants. He then went and washed.
Now whenever we have a sleepover he wants to pull me off even though his is 16cm which is still good, he loves my cock and gives me the best time ever. I have also pulled him off but it isn't as good.