Another party, another cellar - Part 2

What, I hear you ask, could possibly make my eyes widen? At the far end of the cellar I see a full blown sling and a guy is lying in there, his legs up high and pulled back. Another guy is pushing into him seeing to his needs, and both are groaning. I have seen live sex many times before but it still entrances me. As I watch with my friend from the pool, I see another guy take a condom from a large bowl which our host has considerately left out. He slips it on and waits while the other guy continues. After a while longer, the first guy pulls out and the second takes his place. The scene is intoxicating, it is pure, raw sex happening a few feet from me. My pool friend then moves round to the side of the sling and starts to rub and then suck the recipient's cock. He has his eyes closed in understandable ecstasy as he gets fucked and sucked. I watch this scene for several minutes, and as a third guy rubbers up it's clear the sling guy is happy to stay. At this point I decided to leave the cellar for some air, it really was stifflingly hot down there. I climbed up the rickety steps and out into the garden where the cooler air refreshed me. My cock was still hard and I got one or two admiring looks. I sipped a cool beer and calmed down a little as I mingled with the other guests. But after about thirty minutes i was drawn back to those steps leading downwards. I felt more at ease this time as I climbed down. The room was a little less crowded, maybe six there in total. The sling was empty and my heartbeat skipped. I wanted to try it but my biggest fear was someone getting carried away and not playing the condom rule. Once laid back in that thing I knew I wouldn't be able to check. As I touched the sling a younger guy asked me if I was going to try it. When I told him my concern he agreed to keep an eye on things and not to worry. With my heart still beating fast i climbed into the sling and laid back feeling strangely weightless. My younger friend was smiling at me and proudly showing his impressive cock, It was clear his intention was to be first and i was in no position to say no!