What advice can you guys give me on this situation?

My ex- boyfriend's friend asked me if I have boyfriend and I told him no. I think he might ask me out on a date, I already decided that I need to talk to him that it wouldn't be a good idea for us to date cause of his friendship with my ex - boyfriend. He texted me two picture messages: 1. Was of the tweety bird with a heart shape candy with a rose and a saying. 2. A rose that opens up with a saying also. My girl said why don't I date him and I told her that it wouldn't be good idea cause there is going to be drama. She asked me what kind of drama and I told her there is just going to be drama. Who care's what kind of drama its just going to be drama. I never gave him the impression that he has a chance with me, once in a great while we text each other to see how we are doing. Should I talk to him and let him know how I feel? My girl told me that he's not jealous and he's really sweet and gentlemen. The only thing that sucks is that he's 21 yrs. old and I'm 28 yrs. old.What advice can you guys give me on this situation?
Here is one thing to know in life, I know I may be only 16 but here is the thing, I know for a fact Age doesn't matter. So what if he 21. it doesn't matter.