He said he wanted to be casual AFTER we had sex

For context; we have been speaking for months. I enjoy messaging him, flirting, we speak all day when we have chance. We finally got to the day of meeting up, we had sex, it was fun then the day after I suggest going for food or something then he hits me with the ‘I don’t want a relationship or anything serious’ which is absolutely fine, he said he still wants to see me again and enjoys spending time with me and wants to see me again for sex. Which is all great however I feel a little let down he didn’t tell me this before we had sex though as I don’t think I would have had sex if I knew it wasn’t going to go anywhere. I know I should have asked but I just presumed that he wanted this to go somewhere like an idiot, I do appreciate his honesty though. Now I’m in this limbo where I’m like well I could have sex with him casually but I’m also worried I may get attached if I keep messaging him/having intimacy… ugh I’m an idiot.