Talking to older men!!!!

So I met this 21 year old guy... And I'm attracted to him and vise virsa... We talk every now and then and he knows I'm 15 he is ok with that but he wants to wait til I'm legal to go out and I agree don't want to get him locked up... But all convos on a friendly level mostly how our school day went he is in college by time I'm 18 he will be 25 what should I do about this???? Help please!!!