He wants to have sex for the first time?

I been knowing this guy for 4 - 5 years. He is younger than me and I don't do younger guys anywho. He wants to have sex with me and he think I be not serious with him with sex like I am 30 he is 24 or 25 years. One time he told me that he want me because he don't see me . And when he don't see me he gets mad like I not your girlfriend he get upset. But when we do see each other we have a fewer drinks and he comes over and we cuddle watch a movie and that's all about the . He respects me as a woman and I respect that he never focus his self on me. But now he is a cute guy but we never go out because I'm busy he is busy he is in the army and he never do anything. Kind of nervous to do it because we never did it before and I think it will be weird. We talk all the time .