What's going on between us?

I’m 19, he’s 25. In mid-July, we mached on Tinder and had a summer affair.
Everything that was going on with him I was inexperienced with: caresses, kisses, passion and excitement. We spend a lot of wonderful moments together, but in early September he leave in Germany. :) He never promised me any feelings, said that communicating is not going anywhere, I realized that it was just a summer affair and had to be accepted as an adventure, I did not rule out the possibility that we could just be friends. We communicate until now. However, I do not understand the purpose of our communication and our status, can it be that he message me when he bored or feeling alone? Because the last time we met he says, I’d like to have a girlfriend like you in Germany, though obviously you’re more than a girlfriend … I don’t understand what’s going on between us because he flirts with me and show attention?