This is the problem the majority of people have with OLD. The majority of people say they want a relationship - nothing to heavy - well of course not, who would want a heavy relationship with someone they've never met before, that's entirely normal. IMO it's the people who are so incensed with their dates not falling in love with them and promising their lives to them IMMEDIATELY as they stated VERY CLEARLY that they were looking for a serious relationship that are a bit scary. Eek. People who advertise themselves to the masses (because that's essentially what OLD is) as only interested in a 'serious' thing are in my opinion a bit of a red flag in themselves. Anyway. In the absence of a serious thing developing I would say a fair percentage of people are willing to settle for something a bit more casual (i.e. a shag) because, well, it's been a while and they're horny. Now here's the problem. Some people can just do that, just settle for the physical. Most people and I am going to stick my neck out here and say mainly women, will SAY they will settle for more casual, but actually are hoping that the guy they fancy will spend just enough time gazing into their eyes post-sex to fall madly in love. It rarely happens. So I think what I am saying is this. In my opinion and experience:
Most people on OLD may are genuinely looking for a relationship (nothing to heavy of course) but not with just anyone - for that special person - and the odds are that most of the people they date/speak to will just not be it. That works both ways.
Most people in the absence of finding the perfect one will be content with scratching the itch and thats when people get hurt because rarely are people are the same page unless they expressly go on there stating they want casual sex (which conversely makes them a sleaze).
My personal experience of OLD after dipping into it a few times is that the last time I went on it I had been dumped in a really rubbish way and as a usually confident person my self esteem has took a knock. I went on Tinder really for a confident boost and nothing more. Started talking to someone for a month so (absolutely no sexy talk or wanking ) met a month later, slept together the first night - been together about 18 months now. Very happy.
My advice for OP is I suspect he won't want you for a casual thing at this stage as you've kind of already given all your allure away, talking him through the game as it were for free. I'd move on and keep him on the back burner if you're feeling frisky at the end of the phone one night. There's casual and then there's literally blowing your load early doors, where else is there to go with it?