My very first sexual experience was as a senior in hs. My best friend and I had dates over to my house for pizza and a swim. The girls had to be in before midnight so he and I went to my GFs house first, dropped her off then headed to his GFs house to drop her off. When were there in her driveway, they started kissing (we were in my moms Cadillac which had a huge front bench seat). Kissing led to him reaching up her t-shirt then in her pants and then with a wink he got her undressed and started fucking her across my lap. I didn't know what to do really so I just played with her tits and rubbed her belly. Well, when it came time for him to cum he pulled out and shot completely across her chest which was where my hand was... I had his cum all over my hand and wrist. I just froze! But it quickly passed as she swiveled around and said "your turn". I fucked her slow and steady then pulled out and came across her chest too. We did this a few times after that ... so yeah, I've seen straight boy cum!