DANG that's hot! That reminds me of the very first time I ever topped a guy since he did something like that. It wasn't at a gloryhole, I was just cruising the mens' room at a very popular stripmall where I was living then. I wound up getting a VERY good blowjob from a talented older daddy. He was jerking himself off while he sucked me and his pants wound up falling down to his knees. He would suck me until I was about to cum and then he'd stop and let me cool down a bit and then start sucking me again until I was close to cumming. He repeated this several times & was pretty much keeping me right at the verge of almost the "point of no return". After about the 7th or 8th time of him stopping to let me cool off, I finally just stopped watching him suck me and leaned my head back against the wall, closed my eyes and focused on how good his mouth felt on my cock. When it finally dawned on me that it didn't feel like his mouth that had just slid over my cock, there really wasn't anything I could do about it. I'd already passed the tipping point and right when I opened my eyes & saw that it was his ass sliding back & forth over me, I wound up shooting a huge load up inside him before I could even process what he was doing to me. Looking back on it now I can see he had planned it out from the beginning. He had his ass already pre-lubed (at the time I didn't realize what was on the crack of his ass that looked slick & wet. It was probably Vaseline or something), and while he was sucking me, he kept looking up at me. At the time I figured he was just checking me out or something but now I realize he was waiting for me to stop paying attention. Almost as soon as he saw I had closed my eyes & wasn't watching, he stopped sucking me & turned and backed up onto me. Not exactly sure why he didn't just ask me if I wanted to fuck him. Maybe he was really horny for a cock in his ass & didn't want to take "no" for an answer. I get the feeling that I wasn't his first "invoulentary top" either. But it was a damn hot experience to have for my first time fucking ever.